MET INVESTORS SERIES    TRUST SUMMARY PROSPECTUS    May 1, 2011 As amended March 13, 2012

BlackRock High Yield Portfolio

Class A and Class B 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, 2011, and the financial statements of the Portfolio for the year ended December 31, 2010, including notes to the financial statements and financial highlights and the report of the Portfolio’s independent registered public accounting firm, which are included in the Annual Report of the Portfolio, 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 other investors.

Investment Objective

To maximize total return, consistent with income generation and prudent investment management.

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. These fees and expenses are for the year ended December 31, 2010, and are expressed as a percentage of the Portfolio’s average daily net assets over that period. The table and the Example below do not reflect the fees, expenses or withdrawal charges imposed by the Contracts. If Contract expenses were reflected, the fees and expenses in the table and Example would be higher. See the Contract prospectus for a description of those fees, expenses and charges.

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
Management Fee	0.60%	0.60%
Distribution and/or Service (12b-1) Fees	None	0.25%
Other Expenses	0.05%	0.05%
Total Annual Portfolio Operating Expenses	0.65%	0.90%

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 you reinvest all of your dividends and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

	Class A	Class B
1 Year	$67	$92
3 Years	$209	$288
5 Years	$363	$500
10 Years	$812	$1,112

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 98.6% of the average value of its portfolio.

Principal Investment Strategies

BlackRock Financial Management, Inc. (“BlackRock”), subadviser to the Portfolio, invests the Portfolio’s assets, under normal circumstances, primarily in non-investment grade bonds with maturities of ten years or less. The Portfolio will normally invest at least 80% of its assets in high yield bonds, including convertible and preferred securities. The high yield securities (commonly called “junk bonds”) acquired by the Portfolio will generally be in the lower rating categories of the major rating agencies (BB or lower by Standard & Poor’s Ratings Services or Ba or lower by Moody’s Investors Service, Inc.) or will be determined by BlackRock to be of similar quality. Split rated bonds will be considered to have the higher credit rating. The Portfolio may invest up to 10% of its assets in non-dollar denominated bonds of issuers located outside of the United States. The Portfolio’s investment in non-dollar denominated bonds may be on a currency hedged or unhedged basis.

BlackRock evaluates sectors of the high yield market and individual bonds within these sectors. Securities are purchased for the Portfolio when BlackRock determines that they have the potential for above-average total return.

To add additional diversification, BlackRock can invest in a wide range of securities, including corporate bonds, mezzanine investments, collateralized bond obligations (“CBOs”), bank loans and mortgage-backed and asset-backed securities. The Portfolio can also invest, to the extent consistent with its investment goal, in non-U.S. and emerging market securities and currencies. The Portfolio may invest in securities of any rating, and may invest up to 10% of its assets (measured at the time of investment) in distressed securities that are in default or the issuers of which are in bankruptcy. These securities involve considerable risk and have significant uncertainties regarding the issuer’s current or future ability to make interest and principal payments. Typically, BlackRock will invest in distressed securities when it believes they are undervalued.

The BlackRock team may, when consistent with the Portfolio’s investment goal, buy or sell options or futures on a security or an index of securities, or enter into credit default swaps (up to 15% of its assets) and interest rate or foreign currency transactions, including swaps (collectively, commonly known as derivatives). The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset and/or as part of a strategy designed to reduce exposure to other risks, such as interest rate or currency risk. The Portfolio may seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such a reverse repurchase agreements or dollar rolls).

Primary 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 “Primary Risks of Investing in the Portfolio” in the Prospectus, any of which could cause the Portfolio’s return, the price of the Portfolio’s shares or the Portfolio’s yield to fluctuate. Please note that there are many other circumstances that could adversely affect your investment and prevent the Portfolio from reaching its objective, which are not described here.

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 and investor sentiment. Significant disruptions to the financial markets could adversely affect the liquidity and volatility of securities held by the Portfolio.

Interest Rate Risk.    The value of the Portfolio’s investments in fixed income securities may decline when prevailing interest rates rise or increase when interest rates go down. The longer a security’s maturity or duration, the greater its value will change in response to changes in interest rates. The interest earned on the Portfolio’s investments in fixed income securities may decline when prevailing interest rates decline.

Credit and Counterparty Risk.    The value of the Portfolio’s investments may be adversely affected if a security’s credit rating is downgraded; an issuer of an investment held by the Portfolio fails to pay an obligation on a timely basis, otherwise defaults or is perceived by other investors to be less creditworthy; or a counterparty to a derivatives or other transaction with the Portfolio files for bankruptcy, becomes insolvent, or otherwise becomes unable or unwilling to honor its obligation to the Portfolio.

High Yield Debt Security Risk.    High yield debt securities, or “junk” bonds, may be more susceptible to market risk and credit and counterparty risk than investment grade debt securities because issuers of high yield debt securities are less secure financially and their securities are more sensitive to downturns in the economy. In addition, the secondary market for high yield debt securities may not be as liquid as that for more highly rated debt securities.

Foreign Investment Risk.    Investments in foreign securities tend to be more volatile and less liquid than investments in U.S. securities because, among other things, they involve risks relating to political, social and economic developments abroad, as well as risks resulting from differences between the regulations and reporting standards and practices to which U.S. and foreign issuers are subject. To the extent foreign securities are denominated in foreign currencies, their values may be adversely affected by changes in currency exchange rates. All of the risks of investing in foreign securities are typically increased by investing in emerging market countries.

Convertible Securities Risk.     Investments in convertible securities may be subject to market risk, credit and counterparty risk, interest rate risk and other risks associated with investments in equity and fixed income securities, depending on the price of the underlying security and the conversion price. In addition, a convertible security may be bought back by the issuer at a time and a price that is disadvantageous to the Portfolio.

Bank Loan Risk.     Investments in bank loans expose the Portfolio to interest rate risk and the credit and counterparty risk of the underlying borrowers of those loans. No active trading market may exist for certain loans. Moreover, adverse market conditions may impair the liquidity of some actively traded loans. The Portfolio may have difficulty valuing and selling bank loans that are illiquid or are less actively traded. Bank loans are also subject to the risk that issuers will prepay the principal more quickly than expected, which could cause the Portfolio to reinvest the repaid principal in investments with lower yields, thereby exposing the Portfolio to a lower rate of return. The Portfolio’s investments in below investment grade loans and other debt securities expose the Portfolio to greater market risk and credit and counterparty risk than a portfolio that invests only in investment

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grade loans and debt securities. Lower rated securities also may be subject to greater price volatility than higher rated investments.

Mortgage-backed and Asset-backed Securities Risk.    The value of investments in mortgage-backed and asset-backed securities is subject to interest rate risk and credit risk. These securities are also subject to the risk that issuers will prepay the principal more quickly or more slowly than expected, which could cause the Portfolio to invest the proceeds in less attractive investments or increase the volatility of their prices. To the extent mortgage-backed and asset-backed securities held by the Portfolio are backed by lower rated securities, such as sub-prime obligations, or are subordinated to other interests in the same mortgage or asset pool, the likelihood of the Portfolio receiving payments of principal or interest may be substantially limited.

Credit Default Swap Risk.    Credit default swaps may increase credit and counterparty risk (depending on whether the Portfolio is the buyer or seller of the swaps), and they may in some cases be illiquid. Credit default swaps also may be difficult to trade or value, especially in the event of market disruptions. Credit default swap transactions in which the Portfolio is the seller may require that the Portfolio liquidate portfolio securities when it may not be advantageous to do so in order to satisfy its obligations or to meet segregation requirements.

Derivatives Risk.    The Portfolio may invest in derivatives to obtain investment exposure, enhance return or “hedge” or protect its assets from an unfavorable shift in the value or rate of a reference instrument. Derivatives can significantly increase the Portfolio’s exposure to market risk, credit and counterparty risk and other risks. Derivatives may be illiquid and difficult to value. Because of their complex nature, some derivatives may not perform as intended. As a result, the Portfolio may not realize the anticipated benefits from a derivative it holds or it may realize losses. Derivative transactions may create investment leverage, which may increase the Portfolio’s volatility and may require the Portfolio to liquidate portfolio securities when it may not be advantageous to do so.

Past Performance

The information below shows the volatility of the Portfolio’s returns from year to year and how the Portfolio’s average annual returns over time compare with those of a broad-based securities market index. Both the bar chart and table assume reinvestment of dividends and distributions. 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.

The performance shown below is the performance of the Portfolio’s Class A shares. The historical performance shown for the Portfolio’s Class A shares prior to May 1, 2006 is the performance of the Portfolio’s predecessor fund managed by a different investment subadviser. Effective August 21, 2006, BlackRock became the subadviser. Investment performance information prior to that date is attributable to the Portfolio’s former investment subadviser.

The bar chart below shows you the performance of the Portfolio’s Class A shares for the last ten calendar years and indicates how it has varied from year to year. The Portfolio can also experience short-term performance swings as indicated in the high and low quarter information at the bottom of the chart. The table below compares the Portfolio’s average annual compounded total returns for each class with index returns. For more information about indexes, please see “Index Description” in the Prospectus. It is not possible to invest directly in an index.

Year-by-Year Total Return as of December 31 of Each Year

Highest Quarter	2nd – 2009	15.66%
Lowest Quarter	4th – 2008	-18.40%

Average Annual Total Return as of December 31, 2010
	1 Year	5 Years	10 Years	Since Inception	Inception Date
Class A	16.10%	7.88%	7.91%	—	—
Class B	15.77%	—	—	9.83%	4-28-08
Barclays Capital U.S. Corporate High Yield 2% Issuer Capped Index (reflects no deduction for mutual fund fees and expenses)	14.94%	8.91%	9.01%	—

Management

Adviser.    MetLife Advisers, LLC (“MetLife Advisers”) is the Portfolio’s investment adviser. For more information about the Adviser, please see “Additional Information about Management—The Adviser” in the Prospectus and “Investment Advisory and Other Services—The Adviser” in the Statement of Additional Information.

Subadviser.    BlackRock Financial Management, Inc. (the “Subadviser”) is the subadviser to the Portfolio. For more information about the Subadviser, please see “Additional Information about Management—The Subadviser” in the Prospectus and “Investment Advisory and Other Services—The Subadvisers” in the Statement of Additional Information.

Portfolio Managers.    James Keenan, Managing Director of BlackRock, Charlie McCarthy, Managing Director of BlackRock, Mitchell Garfin, Managing Director of BlackRock,

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and Derek Schoenhofen, Director of BlackRock, have managed the Portfolio since 2007, 2012, 2009 and 2009, respectively. For additional information, please see “Additional Information about Management—The Subadviser” in the Prospectus and “Investment Advisory and Other Services—Portfolio Management” in the Statement of Additional Information.

Tax Information

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

Payments to Insurance Companies and Their Affiliates

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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