METROPOLITAN SERIES    FUND SUMMARY PROSPECTUS    May 1, 2016

MetLife Stock Index Portfolio

Class A, Class B, Class D, Class E and Class G Shares

Before you invest, you may want to review the Portfolio’s Prospectus, which contains more information about the Portfolio and its risks. You can find the Portfolio’s Prospectus and other information about the Portfolio (including the documents listed below) online at www.metlife.com/variablefunds. You can also get this information at no cost by calling 1-800-638-7732 or by sending an e-mail request to RCG@metlife.com. The Portfolio’s Prospectus and Statement of Additional Information, both dated May 1, 2016, and the Portfolio’s financial statements for the year ended December 31, 2015, including the notes to the financial statements, the financial highlights and the report of the Portfolio’s independent registered public accounting firm, all of which are included in the Annual Report of the Portfolio, dated December 31, 2015, are all incorporated by reference into this Summary Prospectus. This Summary Prospectus is intended for individuals who have purchased certain variable life insurance policies and variable annuity contracts (collectively, “Contracts”) from Metropolitan Life Insurance Company and its affiliates and is not intended for use by other investors.

Investment Objective

To track the performance of the Standard & Poor’s 500 Composite Stock Price Index (“S&P 500 Index”).

Fees and Expenses of the Portfolio

The following table describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio. The table and the Example below do not reflect the fees, expenses or withdrawal charges imposed by the Contracts. See the Contract prospectus for a description of those fees, expenses and charges. If Contract expenses were reflected, the fees and expenses in the table and Example would be higher.

Shareholder Fees (fees paid directly from your investment)—None

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

	Class A			Class B			Class D			Class E			Class G
Management Fee		0.25%			0.25%			0.25%			0.25%			0.25%
Distribution and/or Service (12b-1) Fees		None			0.25%			0.10%			0.15%			0.30%
Other Expenses		0.02%			0.02%			0.02%			0.02%			0.02%
Total Annual Portfolio Operating Expenses		0.27%			0.52%			0.37%			0.42%			0.57%
Fee Waiver*		(0.01%	)		(0.01%	)		(0.01%	)		(0.01%	)		(0.01%	)
Net Operating Expenses		0.26%			0.51%			0.36%			0.41%			0.56%

* MetLife Advisers, LLC has contractually agreed, for the period May 1, 2016, through April 30, 2017, to reduce the Management Fee for each Class of the Portfolio to the annual rate of 0.25% of the first $500 million of the Portfolio’s average daily net assets, 0.245% of the next $500 million, 0.24% of the next $1 billion and 0.235% of amounts over $2 billion. This arrangement may be modified or discontinued prior to April 30, 2017, only with the approval of the Board of Trustees of the Portfolio.

Example

The following Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year, that the Portfolio’s operating expenses remain the same, and that all fee waivers for the Portfolio will expire after one year. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

	1 Year		3 Years		5 Years		10 Years
Class A	$	27	$	86	$	151	$	343
Class B	$	52	$	166	$	290	$	653
Class D	$	37	$	118	$	207	$	468
Class E	$	42	$	134	$	235	$	530
Class G	$	57	$	182	$	318	$	714

Portfolio Turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual portfolio operating expenses or in the Example, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 9% of the average value of its portfolio.

Principal Investment Strategies

The S&P 500 Index consists of the common stocks of 500 companies, most of which are listed on the New York Stock Exchange. MetLife Investment Advisors, LLC (“MLIA” or “Subadviser”), subadviser to the Portfolio, manages the Portfolio by purchasing the common stocks of all the companies included in the S&P 500 Index. The S&P 500 Index includes stocks issued by 500 leading companies in leading industries of the U.S. economy. The vast majority of companies included in the S&P 500 Index have a large capitalization. Although the Portfolio seeks to track the performance of the S&P 500 Index, its performance usually will not exactly match that of the index because, among other things, the Portfolio incurs operating expenses. The S&P 500 Index is an unmanaged group of common stocks, and therefore

does not incur these expenses. As of December 31, 2015, the market capitalizations of companies in the S&P 500 Index ranged from $1.8 billion to $586.9 billion.

MLIA, under normal circumstances, invests at least 80% of the Portfolio’s net assets in stocks included in a particular stock index. The Portfolio may also invest in real estate investment trusts.

MLIA may rebalance the Portfolio due to, among other things, cash flows into and out of the Portfolio or changes in the S&P 500 Index.

Principal Risks

As with all mutual funds, there is no guarantee that the Portfolio will achieve its investment objective. You could lose money by investing in the Portfolio. An investment in the Portfolio through a Contract is not a deposit or obligation of, or guaranteed by, any bank, and is not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other agency of the U.S. Government.

The value of your investment in the Portfolio may be affected by one or more of the following risks, which are described in more detail in “Principal Risks of Investing in the Portfolio” in the Prospectus, any of which could cause the Portfolio’s return or the price of its shares to decrease or could cause the Portfolio’s yield to fluctuate.

Market Risk.    The Portfolio’s share price can fall because of, among other things, a decline in the market as a whole, deterioration in the prospects for a particular industry or company, or changes in general economic conditions, such as prevailing interest rates or investor sentiment. Significant disruptions to the financial markets could adversely affect the liquidity and volatility of securities held by the Portfolio.

Market Capitalization Risk.    Investing primarily in issuers in one market capitalization category (large, medium or small) carries the risk that due to current market conditions that category may be out of favor with investors. Larger, more established companies may be unable to respond quickly to new competitive challenges or attain the high growth rate of successful smaller companies. Stocks of smaller companies may be more volatile than those of larger companies due to, among other things, narrower product lines, more limited financial resources and fewer experienced managers. In addition, there is typically less publicly available information about small capitalization companies, and their stocks may have a more limited trading market than stocks of larger companies.

Passive Management Risk.    In attempting to track the returns of an index, the Portfolio may be more susceptible to risks because it generally will not use any defensive strategies to mitigate its risk exposure. In addition, the Portfolio’s returns may deviate from the index it seeks to track as a result of, among other things, portfolio operating expenses, transaction costs and delays in investing cash.

Real Estate Investment Risk.    Investments in real estate investment trusts and other real estate related securities may be adversely impacted by the performance of the real estate market generally or that of a particular sub-sector or geographic region.

Past Performance

The information below provides some indication of the risks of investing in the Portfolio by showing changes in the Portfolio’s performance from year to year and how the Portfolio’s average annual returns over time compare with those of a broad-based securities market index. Note that the results in the bar chart and table do not include the effect of Contract charges. If these Contract charges had been included, performance would have been lower. As with all mutual funds, past returns are not a prediction of future returns. On April 30, 2007, MLIA was named subadviser to the Portfolio after MLIA was organized to succeed to certain parts of the investment advisory business of its affiliate, Metropolitan Life Insurance Company. Performance information prior to that date includes results prior to this organizational change.

Year-by-Year Total Return for Class A Shares as of December 31 of Each Year

Highest Quarter	2nd – 2009	15.85%
Lowest Quarter	4th – 2008	-21.95%

Average Annual Total Return as of December 31, 2015
	1 Year			5 Years			10 Years			Since Inception			Inception Date
Class A		1.17	%		12.28	%		7.05	%		—			—
Class B		0.91	%		12.01	%		6.79	%		—			—
Class D		1.07	%		12.18	%		N/A			15.97	%		04-28-09
Class E		1.02	%		12.12	%		6.89	%		—			—
Class G		0.91	%		N/A			N/A			1.88	%		11-12-14
S&P 500 Index (reflects no deduction for mutual fund fees or expenses)		1.38	%		12.57	%		7.31	%		—			—

Management

Adviser.    MetLife Advisers, LLC (“MetLife Advisers”), is the Portfolio’s investment adviser.

Subadviser.    MetLife Investment Advisors, LLC is the subadviser to the Portfolio.

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Portfolio Managers.    Stacey Lituchy, CFA, Director, Norman Hu, Associate Director, and Mirsad Usejnoski, Associate Director, are the managers of the Portfolio. Ms. Lituchy has been the senior manager of the Portfolio since 2004. Mr. Hu has been a manager of the Portfolio since 2003. Mr. Usejnoski has been a manager of the Portfolio since 2004.

Purchase and Sale of Portfolio Shares

Shares of the Portfolio are only sold to separate accounts of Metropolitan Life Insurance Company and its affiliates to fund Contracts. For information regarding the purchase and sale of the Portfolio’s shares, please see the prospectus for the relevant Contract.

Tax Information

For information regarding the tax consequences of Contract ownership, please see the prospectus for the relevant Contract.

Payments to Broker-Dealers and Other Financial Intermediaries

The Portfolio is not sold directly to the general public but instead is offered as an underlying investment option for Contracts issued by insurance companies that are affiliated with the Portfolio and MetLife Advisers. As a result of these affiliations, the insurance companies may benefit more from offering the Portfolio as an investment option in the Contracts than offering other unaffiliated portfolios. The Portfolio and its related companies may also make payments to the sponsoring insurance companies (or their affiliates) for distribution and/or other services. The benefits to the insurance companies of offering the Portfolio over unaffiliated portfolios and these payments may be factors that the insurance companies consider in including the Portfolio as an underlying investment option in the Contracts and may create a conflict of interest. The prospectus for your Contract contains additional information about these payments.

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