August 14, 2019

VIA EDGAR

U.S. Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549    

Attention: Mses. Christina Fettig and Samantha Brutlag

Registration Statement on Form N-14

(File Nos. 333-231804)                                                                                                

Dear Mses. Fettig and Brutlag:

On behalf of BlackRock Funds II (the “Registrant”), this letter responds to the telephonic comments provided by Ms. Christina Fettig on June 19, 2019 and Ms. Samantha Brutlag on June 28, 2019, each of the staff (the “Staff”) of the Securities and Exchange Commission (the “Commission”), regarding the Registrant’s Registration Statement on Form N-14 filed with the Commission on May 29, 2019 (the “Registration Statement”) relating to the proposed acquisition by BlackRock LifePath^® Smart Beta Retirement Fund (the “Acquiring Fund”), a series of the Registrant, of substantially all of the assets and certain stated liabilities of BlackRock LifePath^® Smart Beta 2020 Fund (the “Target Fund”), a series of the Registrant, in exchange for shares of the corresponding Acquiring Fund (the “Reorganization”). The Target Fund and the Acquiring Fund may be referred to herein as a “Fund.” The Acquiring Fund after consummation of the Reorganization is referred to herein as the “Combined Fund.”

The Staff’s comments are described below and have been summarized to the best of our understanding. We have discussed the Staff’s comments with representatives of the Funds. The Funds’ responses to the Staff’s comments are set out immediately under the restated comment. Unless otherwise indicated, defined terms used herein have the meaning set forth in the Registration Statement.

Accounting Comments

General

Comment 1:    Please update the financial highlights, capitalization tables and pro forma financials in the Statement of Additional Information to reflect information as of the most recently completed semi-annual period for the Target Fund and the Acquiring Fund, as applicable.

Response:    In response to the Staff’s comment, the financial highlights, capitalization tables and pro forma financials in the Statement of Additional Information for the Target Fund and the Acquiring Fund, as applicable, have been updated to reflect information as of each Fund’s most recently completed semi-annual period.

Sidley Austin (NY) LLP is a Delaware limited liability partnership doing business as Sidley Austin LLP and practicing in affiliation with other Sidley Austin partnerships.

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Questions & Answers

Comment 2:    In response to the question “Why is the Reorganization taking place?”, please consider including additional disclosure regarding the reasons for the Reorganization.

Response:    In response to the Staff’s comment, the following disclosure has been added to provide additional disclosure regarding the reasons for the Reorganization:

“BlackRock LifePath^® Smart Beta 2020 Fund (the “Target Fund”), a series of BlackRock Funds II (the “Trust”), and BlackRock LifePath^® Smart Beta Retirement Fund (the “Acquiring Fund”), a series of the Trust, are part of the LifePath Smart Beta investment program pursuant to which the Target Fund will have a substantially similar investment objective and identical investment policies, strategies, restrictions and risks as the Acquiring Fund as the target date of the Target Fund approaches in 2020. It is expected that the Reorganization will enable the Combined Fund (as defined below) to operate more efficiently in the future.”

Comment 3:    In response to the question “How will the Reorganization affect Fund fees and expenses?”, please update the response to reflect information as of the most recently completed semi-annual period for the Acquiring Fund.

Response:    In response to the Staff’s comment, the response has been updated to reflect information as of the most recently completed semi-annual period for the Acquiring Fund.

Summary – Investment Objectives and Principal Investment Strategies

Comment 4:    In the section entitled “Summary – Investment Objectives and Principal Investment Strategies – Principal Investment Strategies”, please consider including additional disclosure regarding the principal investment strategies of the Funds.

Response:    In response to the Staff’s comment, the section entitled “Summary – Investment Objectives and Principal Investment Strategies – Principal Investment Strategies” has been modified as follows:

“The Target Fund and the Acquiring Fund employ substantially the same principal investment strategies in seeking to achieve their respective objectives, although there are certain differences.

Each Fund, which is a fund of funds, allocates and reallocates its assets among a combination of equity, fixed income and money market funds (the “underlying funds”) in proportions based on its own comprehensive investment strategy. Under normal

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circumstances, each Fund intends to invest primarily in affiliated open-end funds and affiliated exchange-traded funds. The Target Fund, which initially had a longer time horizon than the Acquiring Fund, invested a greater portion of its assets in underlying funds that invest in equity securities, which provide a greater opportunity for capital appreciation over the long-term but have a greater risk of loss. The Acquiring Fund, which initially had a shorter time horizon than the Target Fund, invested a greater portion of its assets in underlying funds that invest in fixed income, including money market instruments, which typically offer reduced risk and price volatility but forego some potential returns. As the Target Fund approaches its designated time horizon, it systematically seeks to reduce the level of risk by allocating assets more conservatively among the underlying funds. This systematic shift toward more conservative investments is designed to reduce the risk of significant reductions in the value of an investment in the Target Fund as it approaches its stated time horizon.

The investment model adjusts the Target Fund’s risk level by gradually making it more conservative as the year 2020 approaches. The Acquiring Fund is already in its most conservative phase, so its risk level does not change. As the Target Fund reaches its stated time horizon and enters its most conservative phase, the allocation of its assets and its investment strategy is expected to be substantially the same as the Acquiring Fund.”

Summary – Fees and Expenses

Comment 5:    Please confirm whether the fees shown in each fee table represent current fees in accordance with Item 3 of Form N-14.

Response:    The Funds have considered the Staff’s comment and confirm that the fees provided in the above referenced fee tables are current fees in accordance with Item 3 of Form N-14.

Comment 6:    In the fee tables, please confirm that any waivers and/or reimbursements that are subject to recoupment for the Target Fund will not be carried over to the Combined Fund.

Response:    The Funds confirm that no waivers and/or reimbursements of the Target Fund subject to recoupment will be carried over to the Combined Fund.

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Other Information – Capitalization

Comment 7:    Please provide further detail in footnotes regarding any pro forma adjustments to the capitalization tables.

Response:     In response to the Staff’s comment, the footnotes to the capitalization tables have been revised to explain that pro forma adjustments include undistributed income that will be distributed prior to the Reorganization.

Comment 8:    Please consider including a line item to the capitalization tables showing the total net assets of each Fund and the Combined Fund.

Response:     In response to the Staff’s comment, the first paragraph of the section entitled “Other Information — Capitalization” has been amended to include the total net assets of each Fund and the Combined Fund.

Statement of Additional Information – Pro Forma Financial Statements

Comment 9:    The Staff notes that the disclosure on page S-3 states that the “net assets of the Combined Fund reflect the expenses incurred in connection with the Reorganization” while the disclosure on page S-5 states that such expenses will be borne by BlackRock Advisors, LLC (“BAL”) or its affiliates directly or through waivers, as applicable. Please clarify whether any expenses incurred in connection with the Reorganization will be borne by the Funds.

Response:    The Funds confirm that expenses incurred in connection with the Reorganization will not be borne by the Funds but are expected to be borne by BAL or its affiliates directly or through waivers, as applicable, and the disclosure has been revised accordingly.

Comment 10:    The Staff notes that the disclosure states that the Funds have the same expense structure, the same type of fees and the same fee rates. Please provide an explanation for the change in the administration fees as a result of the Reorganization as disclosed on page S-4.

Response:    The Funds confirm that there will be no change in administration fees as a result of the Reorganization and have revised the disclosure accordingly.

Comment 11:    On page S-4, the Staff notes that the disclosure provides that “the total net annual operating expenses for the Combined Fund will be lower than that of the Target Fund” while the chart below such disclosure indicates that the total net annual operating expenses for the Combined Fund will be the same as that of the Target Fund. Please provide an explanation.

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Response:    In response to the Staff’s comment, we have revised the disclosure as follows:

“Upon the closing of the Reorganization, the total net annual operating expenses for the Combined Fund will be the same as those lower than that of the Target Fund.”

Legal Comments

General

Comment 12:    Please explain why a vote of the Target Fund shareholders is not required to be taken in connection with the Reorganization.

Response:    The Reorganization will not require the vote of the Target Fund shareholders under the Registrant’s trust instrument, applicable state law or the Investment Company Act of 1940, as amended (the “1940 Act”), in reliance on Rule 17a-8 under the 1940 Act. Under Rule 17a-8, shareholder approval is not required if: (a) no policy of the target fund that could not be changed under Section 13 of the 1940 Act without a vote of a majority of its outstanding voting securities is materially different from a policy of the acquiring fund; (b) no advisory contract of the target fund is materially different from that of the acquiring fund; (c) the independent directors of the target fund who were elected by shareholders will comprise a majority of the independent directors of the acquiring fund; and (d) any distribution fees under a Rule 12b-1 plan payable by the acquiring fund are no greater than the distribution fees payable by the target fund. The Board of Trustees of the Registrant has determined that each of the conditions listed above is satisfied in the case of the Reorganization.

Comment 13:    Please provide a draft of the legal opinion regarding the legality of the securities being registered and a draft of the tax opinion regarding the status of the Reorganization as a tax-free reorganization under Section 368 of Internal Revenue Code of 1986, as amended, prior to going effective.

Response:    A draft of the legality opinion and a draft of the tax opinion were provided supplementally to the Staff on August 7, 2019.

Comment 14:    Please explain why the Funds are not charged a management fee.

Response:    Each Fund does not pay a management fee because it is a “fund of funds” which allocates and reallocates its assets among a combination of primarily affiliated underlying funds. Each Fund indirectly pays a portion of the management fees incurred by the underlying funds.

Summary – Background and Reasons for the Reorganization

Comment 15:    Please consider combining or revising the first two sentences in the first paragraph of the section entitled “Summary – Background and Reasons for the Reorganization.”

Response:    In response to the Staff’s comment, the first sentence in the first paragraph of the section entitled “Summary – Background and Reasons for the Reorganization” has been deleted.

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Comment 16:    In the section entitled “Summary – Investment Objectives and Principal Investment Strategies – Principal Investment Strategies”, please consider including additional disclosure regarding the investment strategies applicable to a fund in its most conservative phase and a fund in a less conservative phase.

Response:    In response to the Staff’s comment, we have revised the disclosure in the section entitled “Summary – Investment Objectives and Principal Investment Strategies – Principal Investment Strategies” as set forth in the response to Question 4 above.

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Please do not hesitate to contact me at (212) 839-8615 if you have comments or if you require additional information regarding the Registration Statement.

Jessica Herlihy

John A. MacKinnon

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