September 11, 2023

Ms. Alison T. White

U.S. Securities and Exchange Commission

100 F Street, NE

Washington, DC 20549

Dear Ms. White:

This correspondence responds to comments provided by telephone by the staff of the U.S. Securities and Exchange Commission (the “Staff”) pursuant to its review of the pre-effective amendment (the “Amendment”) to the registration statement for Themes ETF Trust (the “Registrant” or the “Trust”), with respect to Themes Airlines ETF, Themes China Technology ETF, Themes Cloud Computing ETF, Themes Cybersecurity ETF, Themes European Luxury ETF, Themes Future of Farming ETF, Themes Generative Artificial Intelligence ETF, Themes Global Systemically Important Banks ETF, Themes Gold Miners ETF, Themes Industry 4.0 ETF, Themes Junior Gold Miners ETF, Themes Natural Monopoly ETF, Themes Renewable Energy ETF, Themes Robotics & Automation ETF, Themes Semiconductors ETF, Themes US Cash Flow Champions ETF, Themes US Internet ETF, Themes US R&D Champions ETF, Themes Silver Miners ETF, Themes Solar Energy ETF, Themes US Small Cap Cash Flow Champions ETF, and Themes Wind Energy ETF (the “Funds”), filed on Form N-1A with the Securities and Exchange Commission on June 30, 2023. For your convenience, the comments have been reproduced with responses following each comment. Changes made to disclosure in the Amendment are redlined in each response as applicable. The captions used below correspond to the captions the Trust uses in the registration statement. All capitalized terms not otherwise defined herein have the meaning given to them in the registration statement.

PROSPECTUS

General

Response: The disclosure has been revised to state that each indexed Fund other than the Themes Natural Monopoly ETF has a policy to invest, under normal circumstances, at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the investment or industry suggested by its name. As an example, the disclosure for the Airlines ETF has been revised as follows:

“In constructing or adjusting the Index, the Index Provider identifies an “Index Universe” of companies that, on Selection Days (as defined below), fulfill the following requirements: … 2) are classified in the Airlines industry by the FactSet Revere Business Industry Classification System (“RBICS”), which includes companies that provide air transportation of passengers, both scheduled (regular routes) and non-scheduled (no regular routes) (“Airline Companies”)…The Fund will invest, under normal circumstances, at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in securities that comprise the Index and in American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”) based on the securities in the Index, and in securities of Airline Companies.”

Response: The Registrant has provided under separate cover a copy of the Index Methodology White Paper and a list of the top ten holdings for the STOXX Global Industry 4.0 Index.

KAREN A. ASPINALL ● PARTNER

11300 Tomahawk Creek Pkwy, Suite 310 ● Leawood, KS 66211

Practus, LLP ● Practus.com

Response: The completed Fees and Expenses Table for each Fund has been provided under separate cover. As an example, the completed Fees and Expenses Table for the Airlines ETF is:

Fees and Expenses of the Fund

The following table describes the fees and expenses you may pay if you buy, hold, and sell shares of the Fund (“Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below.

Example

The following example is intended to help retail investors compare the cost of investing in the Fund with the cost of investing in other funds. It illustrates the hypothetical expenses that such investors would incur over various periods if they were to invest $10,000 in the Fund for the time periods indicated and then redeem all of the Shares at the end of those periods. This example assumes that the Fund provides a return of 5% a year and that operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

Themes Airlines ETF

Response: The Registrant has reviewed its Geographic Risk disclosures and believes the risks related to the Airlines, China Technology, European Luxury, Robotics & Automation, Semiconductor, US Cash Flow Champions, US Internet, US R&D Champions and US Small Cap Cash Flow Champions ETFs are appropriate as currently disclosed. Geographic Risk disclosure for the remaining Funds was revised as follows:

Cloud Computing ETF: Risk of Investing in Asia and Israel were removed.

Cybersecurity ETF: Risk of Investing in Europe was removed.

Future of Farming ETF: Risk of Investing in Israel was removed.

Generative Artificial Intelligence ETF: Risk of Investing in Europe and Asia were removed.

Global Systemically Important Banks ETF: Risk of Investing in Europe was removed.

Gold Miners ETF: Risk of Investing in Brazil, Europe, China, Hong Kong, and South Korea were removed.

Industry 4.0 ETF: Risk of Investing in India, South Korea, and Taiwan were removed.

Junior Gold Miners ETF: Risk of Investing in China, Hong Kong, Africa and the Middle East, Brazil, and South Korea were removed.

Natural Monopoly ETF: Risk of Investing in China, Hong Kong, and Israel were removed.

Renewable Energy ETF: Risk of Investing in Asia, Hong Kong, and Israel were removed.

Silver Miners ETF: Risk of Investing in Europe, Australia, Brazil, South Korea, and Africa and the Middle East were removed.

Solar Energy ETF: Risk of Investing in Australia and Risk of Investing in Africa and the Middle East were removed.

Wind Energy ETF: Risk of Investing in North America, Australia, and Africa and the Middle East were removed.

Themes China Technology ETF

Themes Cybersecurity ETF

Response: An incorrect Index Methodology White Paper was inadvertently provided to the Staff by the Registrant in conjunction with its Correspondence filed on June 30, 2023. The Registrant has provided under separate cover the correct Index Methodology White Paper and list of the top ten holdings for the Solactive Cyber Security Index.

Response: The Registrant has removed the term “significant assets” where noted by the Staff for all applicable Funds.

Response: As noted in the response to Comment 8, the Registrant has removed the references to each of the sub-industries, including those noted in the comment, for clarity and to be consistent with the Index Methodology White Paper.

Themes European Luxury ETF

Response: For all applicable Funds, the Registrant has replaced the disclosure cited with: “If a model or a description prove to be incorrect or incomplete, any decisions made in reliance thereon may lead to the inclusion or exclusion of securities in or from the Index universe that would have been excluded or included had the models and descriptions been correct and complete. If the composition of the Index reflects such errors, the Fund’s portfolio can be expected to also reflect the errors.”

Themes Future of Farming ETF

Response: The Registrant has revised the disclosure to be consistent with the Index Methodology White Paper as follows:

“Companies are only eligible for inclusion in the Index if they generate at least 50% of their revenues or income from, are classified under, or own significant assets in, the agricultural related business operationsindustry.”

Response: The disclosure has been revised to clarify the relationship as follows:

“Based on the Index Universe, the initial composition of the Index, as well as any selection for an ordinary rebalance, is determined on the Selection Day by first screening publicly available information such as financial news, business profiles and company publications using the Index Provider’s proprietary natural language processing algorithm (“ARTIS^®”) to identify companies that have or are expected to have exposure to the provision of products and/or services that contribute to the future innovative and forward-looking aspects of the agricultural industry. The Index Provider identifies relevant search terms for ARTIS^® that best represent the industries and areas of such innovation (i.e., drones, agtech, hydroponics, agricultural robot and farming software). The investment strategy’s focus extends beyond traditional agricultural practices and production to include technology-enabled agricultural processes, encompassing everything from crop monitoring to precision agriculture, digital farming, and smart agriculture - growing trends shaping the future of farming.”

Themes Generative AI ETF

Response: The disclosure has been revised as follows:

“…ontology engineering (i.e., the study of methods and methodologies for building ontologies a set of concepts and categories in a subject area or domain that show their properties and the relations of a set of concepts and categories in a subject areabetween them to allow the AI to make inferences based on content and relationships),…”

Response: For clarity, the disclosure discussing the 1 to 40 ranking has been replaced with: “The Index is rebalanced and reconstituted on each Rebalance Day based on data as of Selection Day. At the time of rebalancing, the Index is generally re-weighted based on the latest ARTIS^® scores.”

Response:

Artificial Intelligence (AI):

Data Analytics and Big Data:

Natural Language Processing:

AI-driven Services:

Themes Industry 4.0 ETF

Response: The disclosure has been revised to define “conversion” in this context as follows:

“Boston Consulting Group analysis found that use of AI can reduce producers’ conversion costs (the cost of changing raw materials into finished goods) by up to 20%.”

Themes Junior Gold Miners ETF

This comment applies to the Robotics & Automation Fund as well.

Response: The disclosure for the Junior Gold Miners ETF has been revised to be consistent with the description of the Index in the Index Methodology White Paper as follows: “1) are a part/component of the STOXX World AC Small Cap Index (a free float market capitalization-weighted index designed to measure the performance of small-capitalization companies, as calculated by the Index Provider, from developed markets and emerging markets covering approximately 15% of the investable market capitalization), excluding companies based in India, United Arab Emirates, Kuwait, and Qatar and Saudi Arabia); 2) have a three month Average Daily Traded Value (ADTV) greater than $1 million and 3) have more than 50% of revenues generated within or income from, are classified under, or own significant assets in, the sectors associated with the gold mining theme as defined by the Index Provider based on FactSet Revere Business Industry Classification System (“RBICS”) Focus and Revenue datasets:…” The description included of the parent index is consistent with the Index Methodology White Paper for that index.

The disclosure for the Robotics & Automation ETF has been revised to be consistent with the description of the Index in the Index Methodology White Paper as follows: “…and 5) be classified in one of the following industries sectors based on the FactSet Revere Business Industry Classification System (“RBICS”) and generate at least 50% of their revenue or income from, are classified under, or own significant assets in, the following industries: Factory Automation Equipment; General Semiconductors; Industrial Machine Parts and Support Equipment; Processor Semiconductors; Programmable Logic and ASIC Semiconductors; and Specialized Conductors (“Robotics and Automation Companies”). In addition, the following has been added to the disclosure: “In order to be classified in one of the above sectors, the RBICS requires that the company generate at least 50% of its revenue from that sector.”

This comment also applies to the Silver Miners ETF.

Response: The Index Methodology White Paper for the STOXX Global Junior Gold Miners Index has been revised to reflect that at least 80% of the Index will consist of companies with 50% or more of their revenues from sectors associated with the gold mining theme. The revised Index Methodology White Paper has been provided under separate cover. The revised Index Methodology will be implemented in December 2023. The Registrant will amend its registration statement to reflect that the Junior Gold Miners ETF will not commence operations until the changes to the Index are fully implemented in December 2023. The second and third paragraphs of the section “Principal Investment Strategies – The Index” for the Junior Gold Miners ETF have been revised accordingly as follows:

“…and 3) have more than 50% or more of revenues generated within or income from, are classified under, or own significant assets in, the sectors associated with the gold mining theme as defined by the Index Provider based on FactSet Revere Business Industry Classification System (“RBICS”) Focus or Revenue datasets: Other North America Gold Ore Mining, Latin America Gold Ore Mining, Pan-Asia Gold Ore Mining, Other Americas Gold Ore Mining, United States Gold Ore Mining, Australia Gold Ore Mining, South Africa Gold Ore Mining, Rest of Asia Gold Ore Mining, China Gold Ore Mining, Canada Gold Ore Mining, Europe Gold Ore Mining, Southeast Asia Gold Ore Mining, Other Africa Gold Ore Mining, Multinational Gold Ore Mining, Multiple Precious Metals Ore Mining and Russia and CIS Gold Ore Mining) (“Junior Gold Mining Companies”)…

The companies in the Index are initially weighted by ranked according to their free float market capitalization. The Index is then capped so that Junior Gold Mining Companies in aggregate weigh a minimum 80% of the Index. In addition…”

For the Silver Miners ETF, the Index Methodology White Paper for the STOXX Global Silver Mining Index has been revised to reflect that at least 80% of the Index will consist of High Exposure Silver Mining Companies, defined as companies with 50% or more of their revenues from sectors associated with the silver mining theme or companies that rank in the top 10 in terms of market share (as defined in the disclosure).The revised Index Methodology White Paper has been provided under separate cover. The revised Index Methodology will be implemented in December 2023. The Registrant will amend its registration statement to reflect that the Silver Miners ETF will not commence operations until the changes to the Index are fully implemented in December 2023. The second and third paragraphs of the section “Principal Investment Strategies – The Index” for the Silver Miners ETF have been revised accordingly as follows:

“The Index Universe is then screened to identify Tier 1 and Tier 2 companies. Tier 1 companies are companies 1) with RBICS Focus of Silver Ore Mining (revenue of 50% or more from the Silver Ore Mining sector), and 2) companies with revenue exposure of 25% or more from the RBICS L6 subindustry of Silver Ore Mining which are ranked by revenue exposure to the subindustry and included in Tier 1 until there are maximum of 50 companies in Teir 1and 3) have significant market share based on absolute revenue (greater than 50%) generated within the Silver Ore Mining sector as defined by FactSet RBICS (the “Index Components”). If the above screening process does not result in at least 50 Index Components, the Index Provider will consider Tier 2 companies are companies that are in the top 40% in terms of market share from Silver Ore Mining not selected as Tier 1 companies Index Components and eligible in terms of their Average Daily Traded Value (“Tier 2”). For this purpose, “market share” is defined by the percentile ranking of all The Tier 2 companies in the Index Universe will consist of companies that maintain significant absolute market share in the Silver Ore Mining sector, as determined by the Index Provider, and have with at least $1 million dollars in revenue generated within the Silver Ore Mining sector to be eligible for inclusion in the Index. The Index Components are then ranked by their revenue exposure from the highest to lowest exposure to the sector. Tier 1 and Tier 2 Companies are included in the Index (“Index Components”).

The Index Components are initially weighted by ranked according to their free float market capitalization. The Index is then capped so that High Exposure Silver Mining Companies weigh in aggregate a minimum of 80% of the Index. “High Exposure Silver Mining Companies” are defined as those with revenue exposure of 50% or more from the RBICS L6 subindustry of Silver Ore Mining, companies with RBICS Focus of Silver Ore Mining (i.e., revenue of 50% or more from the Silver Ore Mining sector), or companies that rank in the top 10 in terms of market share (as defined above) from Silver Ore Mining as identified by the Index Provider. In addition, the maximum Index Component weight is no higher than 810% and companies with a weight over 4.5% do not exceed 45% in aggregation. Tier 2 companies, in aggregate, are capped at 30% of the IndexFund’s portfolio.”

Themes Semiconductors ETF

Response: The Registrant has provided under separate cover a copy of the Index Methodology White Paper for the Solactive GBS (Global Benchmark Series) Global Markets Semiconductor All Cap USD Index GTR.

Themes Silver Miners ETF

This comment also applies to the Solar Energy ETF (see Response #21 below).

Response: See Response #18 above.

Themes Solar Energy ETF

Response: The Index Methodology White Paper for the STOXX Global Solar Energy Index has been revised to reflect that at least 80% of the Index will consist of companies with 50% or more of their revenues from sectors associated with the solar energy theme. The revised Index Methodology White Paper has been provided under separate cover. The revised Index Methodology will be implemented in December 2023. The Registrant will amend its registration statement to reflect that the Solar Energy ETF will not commence operations until the changes to the Index are fully implemented in December 2023. The second and third paragraphs of the section “Principal Investment Strategies – The Index” for the Solar Energy ETF have been revised accordingly as follows:

“…and 4) have more than 50% or more of revenues generated within or income from, own significant assets in, or are classified under the sectors associated with the solar energy theme as defined by the Index Provider based on the FactSet Revere Business Industry Classification System (“RBICS”) Focus and Revenue datasets: (e.g., China Solar Wholesale Power, United States Solar Wholesale Power, Canada Solar Wholesale Power, Latin America Solar Wholesale Power, Europe Solar Wholesale Power, Middle East and Africa Solar Wholesale Power, Other Asia/Pacific Solar Wholesale Power, Photovoltaic and Solar Cells and Systems Providers, and Alternative Energy Infrastructure Construction) (“Solar Energy Companies”)…

The Index Components are initially weighted by ranked according to their free float market capitalization. The Index is then capped so that Solar Energy Companies in aggregate weigh a minimum 80% of the Index. In addition…”

Themes US Internet ETF

Response: The disclosure has been revised to include the phrase “is engaged primarily in” as follows:

“A company is deemed to be an Internet Company by the Index Provider if it meets any of the following definitions: (1) it is engaged primarily participates in internet commerce which includes…”

Response: The Registrant believes that the Index Methodology White Paper provided to the Staff does reflect the substance of the prospectus language cited (please see sections 1, 2.1 and 4), except for the description of the parent index stating that it “intends to track the performance of approximately 3,000 of the largest US equities” which was taken from the Index Methodology White Paper for the parent index. For clarity, the disclosure has been revised to more closely track the Index Methodology White Paper description of the Index as follows:

“…intends to track the performance of approximately 3,000 of the largest US equities); (2) generate the majority (greater than 50%) of their revenues from internet activity (see below for the definition of an “Internet Company”); (3) have minimum free-float market capitalization of $500 million; (4) have a minimum Average Daily Value Traded over the past three months of $2 million. The Average Daily Value Traded for an Index Component is the sum of daily value traded over the specified period divided by the number of trading days that fall in the specified period; and (5) are listed and traded on a national US stock exchange. A company is deemed to be an Internet Company by the Index Provider if it meets any of the following definitions: (1) it is engaged primarily participates in internet commerce which includesin providing for a) the sale of goods (e.g. retail durables like appliances and non-durables like food and cleaning products), 2b) it is engaged in providing a service via internet which includes the sale of services (e.g. banking, broker, payments or real estate; static or streaming media; travel), or c) social networking (e.g. professional, personal or targeted networking) through an open network open networksocial media platform; and/or (32) it is a company engaged in providing Internet-related services, including but not limited to a) network communications, b) Internet access, c) Internet infrastructure, d) Internet software, e)…”

Themes Wind Energy ETF

Response: The Index Methodology White Paper for the STOXX Global Wind Energy Index has been revised to reflect that at least 80% of the Index will consist of companies with 50% or more of their revenues from sectors associated with the wind energy theme. The revised Index Methodology White Paper has been provided under separate cover. The revised Index Methodology will be implemented in December 2023. The Registrant will amend its registration statement to reflect that the Wind Energy ETF will not commence operations until the changes to the Index are fully implemented in December 2023. The second and third paragraphs of the section “Principal Investment Strategies – The Index” for the Wind Energy ETF have been revised accordingly as follows:

“…and 4) have more than 50% or more of revenues generated within or income from, own significant assets in, or are classified under the following sectors associated with the wind energy theme as defined by the Index Provider based on FactSet Revere Business Industry Classification System (“RBICS”) Focus and Revenue datasetsRBICS: (e.g., China Wind Wholesale Power, United States Wind Wholesale Power, Canada Wind Wholesale Power, Europe Wind Wholesale Power, Latin America Wind Wholesale Power, Middle East and Africa Wind Wholesale Power, Other Asia/Pacific Wind Wholesale Power, Wind Energy Equipment Manufacturing, and Alternative Energy Infrastructure Construction) (“Wind Energy Companies”) The Index aims to have a minimum number of 50 Index Componentsconstituents at each review (“Index Components”). If the screening process described above results in being too restrictive, the revenue filter is progressively lowered in steps of 5% for the Index, to a minimum of 30% (25% for current Index Components), until the number of constituents is equal to or greater than 50. This process allows the Fund to obtain access to companies that are considered diversified players (i.e., a company with revenues greater than 25% but less than 50% in the wind distribution and related manufacturing industry) and/or absolute market leaders in the wind distribution and related manufacturing industry. The revenue threshold is lowered to 45% for existing Index Components in order to manage portfolio turnover.

The Index Components are weighted by ranked according to their free float market capitalization. The Index is then capped so that Wind Energy Companies in aggregate weigh a minimum 80% of the Index. In addition…”

Additional Information About the Funds – Additional Information About the ARTIS Scoring System

Response: In the interests of plain english and clarity, the paragraph containing the phrases cited in the comment has been deleted.

Additional Information about the Principal Risks of Investing in the Funds

Response: The disclosure has been separated and given the heading “Calculation Methodology Risk Related to Certain Chinese Companies.”

Additional Information about Buying and Selling Fund Shares

Response: The disclosures in the section “Provisions in the Trust’s Governing Documents Regarding Shareholder Derivative Claims of the prospectus, and “Additional Information Concerning the Trust” in the SAI have been revised as follows:

“As described further in the Declaration of Trust, no person, other than a Trustee, who is not a Shareholder of a particular Series (or class) shall be entitled to bring any derivative action, suit or other proceeding on behalf of the Trust with respect to such Series (or class). No Shareholder of a Series or (or class) may maintain a derivative action on behalf of the Trust with respect to such Series (or class) unless holders of a least ten percent (10%) of the outstanding Shares of such Series (or class) join in the bringing of such action; except that this provision will not apply to claims brought under the U.S. federal securities laws to the extent that any such federal securities laws, rules or regulations, do not permit such application. In addition to the requirements set forth in Section 3816 of the Delaware Act, a Shareholder may bring a derivative action on behalf of the Trust with respect to a Series (or class) only if the following conditions are met: (i) the Shareholder or Shareholders must make a pre-suit demand upon the Trustees to bring the subject action unless an effort to cause the Trustees to bring such an action is not likely to succeed; and a demand on the Trustees shall only be deemed not likely to succeed and therefore excused if a majority of the Trustees, or a majority of any committee established to consider the merits of such action, has a personal financial interest in the transaction at issue, and a Trustee shall not be deemed interested in a transaction or otherwise disqualified from ruling on the merits of a Shareholder demand by virtue of the fact that such Trustee receives remuneration for his service as a Trustee of the Trust or as a trustee or director of one or more investment companies that are under common management with or otherwise affiliated with the Trust; and (ii) unless a demand is not required under clause (i) of this paragraph, the Trustees must be afforded a reasonable amount of time to consider such Shareholder request and to investigate the basis of such claim; and the Trustees shall be entitled to retain counsel or other advisors in considering the merits of the request and may require an undertaking by the Shareholders making such request to reimburse the Trust for the expense of any such advisors in the event that the Trustees determine not to bring such action (except that the provision allowing the Trustees to require an undertaking by the Shareholders to reimburse the Trust for the expense of any such advisors will not apply to claims brought under the U.S. federal securities laws) to the extent that any such federal securities laws, rules or regulations, do not permit such application).”

SIGNATURES

Response: The Registrant represents that all future pre-effective amendments to the Registrant’s registration statement will be signed by the Trust’s principal accounting officer or comptroller, or a person(s) performing similar functions in accordance with Section 6(a) of the Securities Act.

If you have any questions regarding the above responses, please do not hesitate to contact Tina Bloom at (513) 708-6391 or Tina.Bloom@practus.com, Wade Bridge at (513) 304-5605 or Wade.Bridge@Practus.com, or me at (949) 629-3928 or Karen.Aspinall@practus.com.