SUMMARY PROSPECTUS    May 1, 2021

AB Variable Products Series Fund, Inc.

Intermediate Bond Portfolio—Class B

Before you invest, you may want to review the Portfolio’s Prospectus, which contains more information about the Portfolio and its risks. The Portfolio’s Prospectus and Statement of Additional Information, both dated May 1, 2021, as may be amended or supplemented, are incorporated by reference into this Summary Prospectus. For free paper or electronic copies of the Portfolio’s Prospectus, reports to shareholders and other information about the Portfolio, go to www.abfunds.com/go/prospectus, email a request to prorequest@alliancebernstein.com, call (800) 227-4618, or ask any insurance company that offers shares of the Portfolio.

As of May 1, 2021, as permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio’s shareholder reports from the insurance company that offers your contract unless you have specifically requested paper copies from the insurance company or from your financial intermediary. Instead of delivering paper copies of the reports, the insurance company may choose to make the reports available on a website, and will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.

You may elect to receive all future reports in paper free of charge from the insurance company. You can inform the insurance company or your financial intermediary that you wish to continue receiving paper copies of your shareholder reports by following the instructions provided by the insurance company or by contacting your financial intermediary. Your election to receive reports in paper will apply to all portfolio companies available under your contract with the insurance company.

INVESTMENT OBJECTIVE

The Portfolio’s investment objective is to generate income and price appreciation without assuming what the Adviser considers undue risk.

FEES AND EXPENSES OF THE PORTFOLIO

This table describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio. Because the information does not reflect deductions at the separate account level or contract level for any charges that may be incurred under a contract, Contractholders that invest in the Portfolio should refer to the variable contract prospectus for a description of fees and expenses that apply to Contractholders. Inclusion of these charges would increase the fees and expenses provided below.

Shareholder Fees (fees paid directly from your investment)

N/A

Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Management Fees	.45%
Distribution (12b-1) Fees	.25%
Other Expenses:
Transfer Agent	.01%
Other Expenses	.81%
Total Other Expenses	.82%
Total Portfolio Operating Expenses	1.52%

Examples

The Examples are intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The Examples assume that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your

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shares at the end of those periods. The Examples also assume that your investment has a 5% return each year and that the Portfolio’s operating expenses stay the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

After 1 Year	$	155
After 3 Years	$	480
After 5 Years	$	829
After 10 Years	$	1,813

Portfolio Turnover

The Portfolio pays transaction costs, such as commissions, when it buys or sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These transaction costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Examples, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 89% of the average value of its portfolio.

PRINCIPAL STRATEGIES

The Portfolio invests, under normal circumstances, at least 80% of its net assets in fixed-income securities. The Portfolio expects to invest in readily marketable fixed-income securities with a range of maturities from short- to long-term and relatively attractive yields that do not involve undue risk of loss of capital. The Portfolio expects to invest in fixed-income securities with a dollar-weighted average maturity of between three to ten years and an average duration of three to six years. The Portfolio may invest up to 25% of its net assets in below investment grade bonds (commonly known as “junk bonds”). The Portfolio may use leverage for investment purposes.

The Portfolio may invest without limit in U.S. Dollar-denominated foreign fixed-income securities and may invest up to 25% of its assets in non-U.S. Dollar-denominated foreign fixed-income securities. These investments may include, in each case, developed and emerging market debt securities.

The Adviser selects securities for purchase or sale based on its assessment of the securities’ risk and return characteristics as well as the securities’ impact on the overall risk and return characteristics of the Portfolio. In making this assessment, the Adviser takes into account various factors, including the credit quality and sensitivity to interest rates of the securities under consideration and of the Portfolio’s other holdings.

The Portfolio may invest in mortgage-related and other asset-backed securities, loan participations and assignments, inflation-indexed securities, structured securities, variable, floating and inverse floating-rate instruments, and preferred stock, and may use other investment techniques. The Portfolio intends, among other things, to enter into transactions such as reverse repurchase agreements and dollar rolls. The Portfolio may invest, without limit, in derivatives, such as options, futures contracts, forwards and swaps.

PRINCIPAL RISKS

• Market Risk: The value of the Portfolio’s assets will fluctuate as the stock or bond market fluctuates. The value of its investments may decline, sometimes rapidly and unpredictably, simply because of economic changes or other events, including public health crises (including the occurrence of a contagious disease or illness), that affect large portions of the market.

• Interest Rate Risk: Changes in interest rates will affect the value of investments in fixed-income securities. When interest rates rise, the value of existing investments in fixed-income securities tends to fall and this decrease in value may not be offset by higher income from new investments. Interest rate risk is generally greater for fixed-income securities with longer maturities or durations. Very low or negative interest rates would likely magnify the risks associated with changes in interest rates. During periods of very low or negative rates, the Portfolio’s returns would likely be adversely affected.

• Credit Risk: An issuer or guarantor of a fixed-income security, or the counterparty to a derivatives or other contract, may be unable or unwilling to make timely payments of interest or principal, or to otherwise honor its obligations. The issuer or guarantor may default, causing a loss of the full principal amount of a security and accrued interest. The degree of risk for a particular security may be reflected in its credit rating. There is the possibility that the credit rating of a fixed-income security may be downgraded after purchase, which may adversely affect the value of the security.

• Below Investment Grade Security Risk: Investments in fixed-income securities with lower ratings (“junk bonds”) tend to have a higher probability that an issuer will default or fail to meet its payment obligations. These securities may be subject to greater price volatility due to such factors as specific corporate developments, interest rate sensitivity and negative perceptions of the junk bond market generally, and may be more difficult to trade than other types of securities.

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• Duration Risk: Duration is a measure that relates the expected price volatility of a fixed-income security to changes in interest rates. The duration of a fixed-income security may be shorter than or equal to full maturity of a fixed-income security. Fixed-income securities with longer durations have more risk and will decrease in price as interest rates rise.

• Inflation Risk: This is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Portfolio’s assets can decline as can the value of the Portfolio’s distributions. This risk is significantly greater if the Portfolio invests a significant portion of its assets in fixed-income securities with longer maturities.

• Foreign (Non-U.S.) Risk: Investments in securities of non-U.S. issuers may involve more risk than those of U.S. issuers. These securities may fluctuate more widely in price and may be more difficult to trade due to adverse market, economic, political, regulatory or other factors.

• Emerging Market Risk: Investments in emerging market countries may have more risk because the markets are less developed and less liquid, and because these investments may be subject to increased economic, political, regulatory or other uncertainties.

• Currency Risk: Fluctuations in currency exchange rates may negatively affect the value of the Portfolio’s investments or reduce its returns.

• Mortgage-Related and/or Other Asset-Backed Securities Risk: Investments in mortgage-related and other asset-backed securities are subject to certain additional risks. The value of these securities may be particularly sensitive to changes in interest rates. These risks include “extension risk”, which is the risk that, in periods of rising interest rates, issuers may delay the payment of principal, and “prepayment risk”, which is the risk that in periods of falling interest rates, issuers may pay principal sooner than expected, exposing the Portfolio to a lower rate of return upon reinvestment of principal. Mortgage-backed securities offered by nongovernmental issuers and other asset-backed securities may be subject to other risks, such as higher rates of default in the mortgages or assets backing the securities or risks associated with the nature and servicing of mortgages or assets backing the securities.

• Leverage Risk: To the extent the Portfolio uses leveraging techniques, its net asset value may be more volatile because leverage tends to exaggerate the effect of changes in interest rates and any increase or decrease in the value of the Portfolio’s investments.

• Illiquid Investments Risk: Illiquid investments risk exists when certain investments are or become difficult to purchase or sell. Difficulty in selling such investments may result in sales at disadvantageous prices affecting the value of your investment in the Portfolio. Causes of illiquid investments risk may include low trading volumes, large positions and heavy redemptions of Portfolio shares. Illiquid investments risk may be higher in a rising interest rate environment, when the value and liquidity of fixed-income securities generally decline.

• Derivatives Risk: Derivatives may be difficult to price or unwind and leveraged so that small changes may produce disproportionate losses for the Portfolio. Derivatives, especially over-the-counter derivatives, are also subject to counterparty risk.

• Management Risk: The Portfolio is subject to management risk because it is an actively-managed investment fund. The Adviser will apply its investment techniques and risk analyses in making investment decisions for the Portfolio, but there is no guarantee that its techniques will produce the intended results. Some of these techniques may incorporate, or rely upon, quantitative models, but there is no guarantee that these models will generate accurate forecasts, reduce risk or otherwise perform as expected.

As with all investments, you may lose money by investing in the Portfolio.

BAR CHART AND PERFORMANCE INFORMATION

The bar chart and performance information provide an indication of the historical risk of an investment in the Portfolio by showing:

• how the Portfolio’s performance changed from year to year over ten years; and

• how the Portfolio’s average annual returns for one, five and ten years compare to those of a broad-based securities market index.

The performance information does not take into account separate account charges. If separate account charges were included, an investor’s return would be lower. The Portfolio’s past performance, of course, does not necessarily indicate how it will perform in the future.

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Bar Chart

During the period shown in the bar chart, the Portfolio’s:

Best Quarter was up 5.82%, 2nd quarter, 2020; and Worst Quarter was down -2.92%, 1st quarter, 2020.

Performance Table

Average Annual Total Returns

(For the periods ended December 31, 2020)

	1 Year		5 Years		10 Years
Portfolio		5.64%		4.01%		3.56%
Bloomberg Barclays U.S. Aggregate Bond Index (reflects no deduction for fees, expenses, or taxes)		7.51%		4.44%		3.84%

INVESTMENT ADVISER

AllianceBernstein L.P. is the investment adviser for the Portfolio.

PORTFOLIO MANAGERS

The following table lists the persons responsible for day-to-day management of the Portfolio’s portfolio:

Employee	Length of Service	Title
Michael Canter	Since 2016	Senior Vice President of the Adviser
Shawn E. Keegan	Since 2007	Senior Vice President of the Adviser
Janaki Rao	Since 2019	Senior Vice President of the Adviser

PURCHASE AND SALE OF PORTFOLIO SHARES

The Portfolio offers its shares through the separate accounts of participating life insurance companies (“Insurers”). You may only purchase and sell shares through these separate accounts. See the prospectus of the separate account of the Insurer for information on the purchase and sale of the Portfolio’s shares.

TAX INFORMATION

The Portfolio may pay income dividends or make capital gains distributions. The income and capital gains distributions are expected to be made in shares of the Portfolio. See the prospectus of the separate account of the Insurer for federal income tax information.

PAYMENTS TO INSURERS AND OTHER FINANCIAL INTERMEDIARIES

If you purchase shares of the Portfolio through an Insurer or other financial intermediary, the Portfolio and its related companies may pay the intermediary for the sale of Portfolio shares and related services. These payments may create a conflict of interest by influencing the Insurer or other financial intermediary and your salesperson to recommend the Portfolio over another investment. Ask your salesperson or visit your financial intermediary’s website for more information.

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