Morgan Stanley Institutional Fund, Inc.

Global Infrastructure Portfolio

Summary Prospectus | April 28, 2023

Share Class and Ticker Symbol

Class IR

MRGOX

Before you invest, you may want to review the Fund’s statutory prospectus (“Prospectus”), which contains more information about the Fund and its risks. You can find the Fund’s Prospectus and other information about the Fund, including the Statement of Additional Information (“SAI”) and the most recent Annual and Semi-Annual Reports to Shareholders (“Shareholder Reports”), online at www.morganstanley.com/im/MSIFGlobalInfrastructureIR. You can also get this information at no cost by calling toll-free 1-866-414-6349 or by sending an e-mail request to orders@mysummaryprospectus.com. The Fund’s Prospectus and SAI, both dated April 28, 2023 (as may be supplemented from time to time), are incorporated by reference into this Summary Prospectus.

Investment Objective

The Global Infrastructure Portfolio (the “Fund”) seeks to provide both capital appreciation and income.

Fees and Expenses

The table below describes the fees and expenses that you may pay if you buy, hold and sell Class IR shares of the Fund. The Fund does not charge any sales loads or other fees when you purchase or redeem Class IR shares. You may pay fees other than the fees and expenses of the Fund, such as brokerage commissions and other fees charged by financial intermediaries, which are not reflected in the tables and examples below.

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


	Class IR
Advisory Fee	0.85%
Distribution and/or Shareholder Service (12b-1) Fee	None
Other Expenses	17.32%
Total Annual Fund Operating Expenses¹	18.17%
Fee Waiver and/or Expense Reimbursement¹	17.23%
Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement¹	0.94%

Morgan Stanley Institutional Fund, Inc. Prospectus | Fund Summary

Global Infrastructure Portfolio (Con’t)

Example

The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The example assumes that you invest $10,000 in the Fund, your investment has a 5% return each year and the Fund’s operating expenses remain the same (except that the example incorporates the fee waiver and/or expense reimbursement arrangement for only the first year). Although your actual costs may be higher or lower, based on these assumptions your costs would be:


If You SOLD Your Shares
	1 Year	3 Years	5 Years	10 Years
Class IR	$ 96	$ 3,396	$ 5,884	$ 9,745


If You HELD Your Shares
	1 Year	3 Years	5 Years	10 Years
Class IR	$ 96	$ 3,396	$ 5,884	$ 9,745

The Fund’s “Adviser,” Morgan Stanley Investment Management Inc., has agreed to reduce its advisory fee and/or reimburse the Fund so that Total Annual Fund Operating Expenses, excluding acquired fund fees and expenses (as applicable), certain investment related expenses, taxes, interest and other extraordinary expenses (including litigation), will not exceed 0.94% for Class IR. The fee waivers and/or expense reimbursements will continue for at least one year from the date of this Prospectus or until such time as the Board of Directors of Morgan Stanley Institutional Fund, Inc. (the “Company”) acts to discontinue all or a portion of such waivers and/or reimbursements when it deems such action is appropriate.

Portfolio Turnover

The Fund 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 and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Total Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 57% of the average value of its portfolio.

Principal Investment Strategies

The Adviser seeks to provide both capital appreciation and income by investing primarily in equity securities issued by companies located throughout the world that are engaged in the infrastructure business. Using internal proprietary research, the Adviser seeks to identify public infrastructure companies that are believed to offer the best value relative to their underlying assets and growth prospects.

The Fund normally invests at least 80% of its assets in equity securities issued by companies located throughout the world that are engaged in the infrastructure business. This policy may be changed without shareholder approval; however, you would be notified upon 60 days’ notice in writing of any changes. A company is considered to be in the infrastructure business if it derives at least 50% of its revenues or earnings from, or devotes at least 50% of its assets to, infrastructure-related activities. Infrastructure refers to the systems and networks of energy, transportation, communication, utilities and other services required for the normal function of society. Companies in the infrastructure business may be involved in a variety of areas, including, but not limited to, (i) the transmission, distribution, storage or transportation of electricity, oil and gas (and other bulk liquid products), water, and other natural resources used to produce energy, (ii) the construction and operation of renewable power facilities, (iii) the development, ownership, lease, concession, or management of highways, toll roads, tunnels, bridges, pipelines, airports, marine ports, refueling and related facilities, (iv) the provision of communications, including the development, lease, concession, or management of telephone, broadcast and mobile towers, fiber optic/copper cable, and satellite networks, (v) waste-water management, water purification/desalination, and other waste operations and (vi) the construction or operation of essential public structures. The Fund’s equity investments may include real estate investment trusts (“REITs”) and convertible securities. The Fund’s investments may include securities of small and medium capitalization companies. The Fund may invest up to 100% of its total assets in foreign securities, which may include emerging market securities. Under normal market conditions, the Fund typically invests at least the lesser of (i) 40% of its total assets in the securities of issuers located outside of the United States or (ii) an amount of its total assets equal to the approximate percentage of issuers located outside of the United States included in the Dow Jones Brookfield Global Infrastructure Index^SM, unless the Adviser determines, in its sole discretion, that conditions are not favorable. If the Adviser determines that conditions are not favorable, the Fund may invest under 40% of its total assets in the securities of issuers located outside of the United States, provided that the Fund will not invest less than 30% of its total assets in such securities except for temporary defensive purposes. In addition, under normal market conditions, the Fund invests in the securities of issuers from at least three different countries, which may include the United States.

The Fund’s Adviser may consider information about environmental, social and governance issues (also referred to as ESG) in its bottom-up stock selection process when making investment decisions. The Fund’s Adviser may engage with company management regarding corporate governance practices as well as what the Fund’s Adviser deems to be materially important environmental and/or social issues facing a company.

The Fund’s Adviser shifts the Fund’s assets between the different types of companies in the infrastructure business described above based on relative valuation, underlying company fundamentals, and demographic and macroeconomic considerations. The Fund has

Morgan Stanley Institutional Fund, Inc. Prospectus | Fund Summary

Global Infrastructure Portfolio (Con’t)

a fundamental policy (i.e., one that cannot be changed without shareholder approval) of investing 25% or more of its total assets in the infrastructure industry.

In selecting securities to buy, hold or sell for the Fund, the Adviser actively manages the Fund using a combination of bottom-up and top-down methodologies. The value-driven approach to bottom-up security selection utilizes proprietary research models to identify infrastructure companies that offer the best value relative to their underlying assets and growth prospects. The top-down allocation provides exposure to major economic infrastructure sectors and countries, with an overweighting to those sectors/countries that offer the best relative valuation. The Adviser generally considers selling a portfolio holding when it determines that the holding no longer satisfies its investment criteria.

Principal Risks

There is no assurance that the Fund will achieve its investment objective, and you can lose money investing in this Fund. The principal risks of investing in the Fund include:

•

Infrastructure Industry. By concentrating its investments in the infrastructure industry, the Fund has greater exposure to the potential adverse economic, regulatory, political and other changes affecting companies operating within such industry. Companies within the infrastructure industry are subject to a variety of factors that may adversely affect their business or operations, including high interest costs in connection with capital construction and improvement programs, high leverage, costs associated with compliance with and changes in environmental and other regulations, difficulty in raising capital in adequate amounts and on reasonable terms in periods of high inflation and unsettled capital markets or government budgetary constraints that impact publicly funded projects, the effects of economic slowdown or recession and surplus capacity, increased competition from other providers of services, uncertainties concerning the availability of fuel at reasonable prices, the effects of energy conservation policies and other factors.

Other factors that may affect the operations of companies within the infrastructure industry include innovations in technology that could render the way in which a company delivers a product or service obsolete, significant changes to the number of ultimate end-users of a company’s products, inexperience with and potential losses resulting from a developing deregulatory environment, increased susceptibility to terrorist attacks, risks of environmental damage due to a company’s operations or an accident, and general changes in market sentiment towards infrastructure and utilities assets. Companies operating in the infrastructure industry face operating risks, including the risk of fire, explosions, leaks, mining and drilling accidents or other catastrophic events. In addition, natural risks, such as earthquakes, floods, lightning, hurricanes, tsunamis and wind, are inherent risks in infrastructure company operations.

•

Equity Securities. In general, prices of equity securities are more volatile than those of fixed-income securities. The prices of equity securities fluctuate, and sometimes widely fluctuate, in response to activities specific to the issuer of the security as well as factors unrelated to the fundamental condition of the issuer, including general market, economic, political conditions and public health conditions. To the extent that the Fund invests in convertible securities, and the convertible security’s investment value is greater than its conversion value, its price will be likely to increase when interest rates fall and decrease when interest rates rise. If the conversion value exceeds the investment value, the price of the convertible security will tend to fluctuate directly with the price of the underlying security. During periods when equity securities experience heightened volatility, such as during periods of market, economic or financial uncertainty or distress, the Fund’s investments in equity securities may be subject to heightened risks.

•

Small and Mid Cap Companies. Investments in small and mid cap companies may involve greater risks than investments in larger, more established companies. The securities issued by small and mid cap companies may be less liquid and such companies may have more limited markets, financial resources and product lines, and may lack the depth of management of larger companies.

•

Foreign and Emerging Market Securities. Investments in foreign markets entail special risks such as currency, political (including geopolitical), economic and market risks. There also may be greater market volatility, less reliable financial information, less stringent investor protections and disclosure standards, higher transaction and custody costs, decreased market liquidity and less government and exchange regulation associated with investments in foreign markets. In addition, investments in certain foreign markets that have historically been considered stable may become more volatile and subject to increased risk due to ongoing developments and changing conditions in such markets. Moreover, the growing interconnectivity of global economies and financial markets has increased the probability that adverse developments and conditions in one country or region will affect the stability of economies and financial markets in other countries or regions. Certain foreign markets may rely heavily on particular industries or foreign capital and are more vulnerable to diplomatic developments, the imposition of economic sanctions against a particular country or countries, organizations, companies, entities and/or individuals, changes in international trading patterns, trade barriers and other protectionist or retaliatory measures. Investments in foreign markets may also be adversely affected by governmental actions such as the imposition of capital controls, nationalization of companies or industries, expropriation of assets or the imposition of punitive taxes. The governments of certain countries may prohibit or impose substantial restrictions on foreign investing in their capital markets or in certain sectors or industries. In addition, a foreign government may limit or cause delay in the convertibility or repatriation of its currency which would adversely affect the U.S. dollar value and/or liquidity of investments denominated in that currency. Certain foreign investments may become less liquid in response to market developments or adverse investor perceptions, or become illiquid after purchase by the Fund, particularly during periods of market turmoil. When the Fund holds illiquid investments, its portfolio may be harder to value. The risks of investing in emerging market countries are greater than the risks associated with investments in foreign developed countries. Certain emerging market countries may be subject to less stringent requirements regarding accounting, auditing, financial reporting and record keeping and therefore, material information related to an investment may not be available or reliable. In addition, the Fund is limited in its

Morgan Stanley Institutional Fund, Inc. Prospectus | Fund Summary

Global Infrastructure Portfolio (Con’t)

ability to exercise its legal rights or enforce a counterparty’s legal obligations in certain jurisdictions outside of the United States, in particular, in emerging market countries. In addition, the Fund’s investments in foreign issuers may be denominated in foreign currencies and therefore, to the extent unhedged, the value of those investments will fluctuate with U.S. dollar exchange rates. To the extent hedged by the use of foreign currency forward exchange contracts, the precise matching of the foreign currency forward exchange contract amounts and the value of the securities involved will not generally be possible because the future value of such securities in foreign currencies will change as a consequence of market movements in the value of those securities between the date on which the contract is entered into and the date it matures. There is additional risk that such transactions may reduce or preclude the opportunity for gain if the value of the currency should move in the direction opposite to the position taken and that foreign currency forward exchange contracts create exposure to currencies in which the Fund’s securities are not denominated. The use of foreign currency forward exchange contracts involves the risk of loss from the insolvency or bankruptcy of the counterparty to the contract or the failure of the counterparty to make payments or otherwise comply with the terms of the contract. Economic sanctions or other similar measures may be, and have been, imposed against certain countries, organizations, companies, entities and/or individuals. Economic sanctions and other similar measures could, among other things, effectively restrict or eliminate the Fund’s ability to purchase or sell securities, negatively impact the value or liquidity of the Fund’s investments, significantly delay or prevent the settlement of the Fund’s securities transactions, force the Fund to sell or otherwise dispose of investments at inopportune times or prices, or impair the Fund’s ability to meet its investment objective or invest in accordance with its investment strategies.

•

REITs. Investing in REITs exposes investors to the risks of owning real estate directly and investing in companies in the real estate industry, as well as to risks that relate specifically to the way in which REITs are organized and operated. For example, the value of these securities may decline when interest rates rise and will also be affected by the real estate market and by the management or development of the underlying properties, which may also be subject to mortgage loans and the underlying mortgage loans may be subject to the risks of default. Operating REITs requires specialized management skills and the Fund indirectly bears management expenses along with the direct expenses of the Fund. REITs are also subject to certain provisions under federal tax law and the failure of a company to qualify as a REIT could have adverse consequences for the Fund. Certain infrastructure companies in which the Fund may invest may elect to be treated as a REIT for U.S. tax purposes, and would therefore be subject to the risks discussed above.

•

Non-Diversification. The Fund is non-diversified, which means that the Fund may invest a greater percentage of its assets in a smaller number of issuers than a diversified fund. Because the Fund is non-diversified, it may be more susceptible to an adverse event affecting a single issuer or portfolio investment than a diversified portfolio and a decline in the value of that issuer’s securities or that portfolio investment may cause the Fund’s overall value to decline to a greater degree than a diversified portfolio.

•

Market and Geopolitical Risk. The value of your investment in the Fund is based on the values of the Fund’s investments, which may change due to economic and other events that affect markets generally, as well as those that affect particular regions, countries, industries, companies or governments. These events may be sudden and unexpected, and could adversely affect the liquidity of the Fund’s investments, which may in turn impact valuation, the Fund’s ability to sell securities and/or its ability to meet redemptions. The risks associated with these developments may be magnified if certain social, political, economic and other conditions and events (such as war, natural disasters, epidemics and pandemics, terrorism, conflicts, social unrest, recessions, inflation, rapid interest rate changes and supply chain disruptions) adversely interrupt the global economy and financial markets. It is difficult to predict when events affecting the U.S. or global financial markets may occur, the effects that such events may have and the duration of those effects (which may last for extended periods). These events may negatively impact broad segments of businesses and populations and have a significant and rapid negative impact on the performance of the Fund’s investments, adversely affect and increase the volatility of the Fund’s share price and exacerbate pre-existing risks to the Fund.

•

Active Management Risk. In pursuing the Fund’s investment objective, the Adviser has considerable leeway in deciding which investments to buy, hold or sell on a day-to-day basis, and which trading strategies to use. For example, the Adviser, in its discretion, may determine to use some permitted trading strategies while not using others. The success or failure of such decisions will affect the Fund’s performance.

•

ESG Investment Risk. The Fund’s adherence to its ESG criteria and application of related analyses when selecting investments may impact the Fund’s performance, including relative to similar funds that do not adhere to such criteria or apply such analyses. Additionally, the Fund’s adherence to its ESG criteria and application of related analyses in connection with identifying and selecting investments may require subjective analysis and may be difficult if data about a particular company is limited. A company’s ESG practices or the Adviser’s assessment of such may change over time.

Shares of the Fund are not bank deposits and are not guaranteed or insured by the Federal Deposit Insurance Corporation or any other government agency.

Morgan Stanley Institutional Fund, Inc. Prospectus | Fund Summary

Global Infrastructure Portfolio (Con’t)

Performance Information

The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s Class IR shares’ performance from year-to-year and by showing how the Fund’s average annual returns for the past one year period and since inception compare with those of broad measures of market performance, as well as an index that represents a group of similar mutual funds, over time. The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available online at www.morganstanley.com/im or by calling toll-free (800) 869-6397.

Annual Total Returns—Calendar Years


High Quarter	03/31/19	14.05%
Low Quarter	03/31/20	-18.23%

Average Annual Total Returns

(for the calendar periods ended December 31, 2022)


	Past One Year	Since Inception
Class IR (commenced operations on 6/15/2018 )
Return Before Taxes	-8.38%	5.22%
Return After Taxes on Distributions¹	-11.71%	2.77%
Return After Taxes on Distributions and Sale of Fund Shares	-2.36%	3.69%
Dow Jones Brookfield Global Infrastructure IndexSM (reflects no deduction for fees, expenses or taxes)²	-6.62%	5.73%³
Lipper Global Infrastructure Funds Index (reflects no deduction for taxes)⁴	-6.80%	5.81%³

1	These returns do not reflect any tax consequences from a sale of your shares at the end of each period.

The Dow Jones Brookfield Global Infrastructure Index^SM is a float-adjusted market capitalization weighted index that measures the stock performance of companies that exhibit strong infrastructure characteristics. The index intends to measure all sectors of the infrastructure market. It is not possible to invest directly in an index.

3	Since Inception reflects the inception date of Class IR.

4	The Lipper Global Infrastructure Funds Index is an equally-weighted performance index of the largest qualifying funds (based on net assets) in the Lipper Global Infrastructure Funds classification. There are currently 10 funds represented in this index.

The after-tax returns shown in the table above are calculated using the historical highest individual federal marginal income tax rates during the period shown and do not reflect the impact of state and local taxes. After-tax returns for the Fund’s other classes will vary from Class IR shares’ returns. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown, and after-tax returns are not relevant to investors who hold their Fund shares through tax deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns may be higher than before-tax returns due to an assumed benefit from capital losses that would have been realized had Fund shares been sold at the end of the relevant periods, as applicable.

Fund Management

Adviser. Morgan Stanley Investment Management Inc.

Portfolio Managers. The Fund is managed by members of the Global Listed Real Assets team. Information about the member primarily responsible for the day-to-day management of the Fund is shown below:


Name	Title with Adviser	Date Began Managing Fund
Matthew King	Managing Director	September 2010

Morgan Stanley Institutional Fund, Inc. Prospectus | Fund Summary

Global Infrastructure Portfolio (Con’t)

Purchase and Sale of Fund Shares

To purchase Class IR shares, an investor must meet a minimum initial investment of $5 million or be a defined contribution, defined benefit or other employer sponsored employee benefit plan, in each case provided that the plan trades through an intermediary that combines its clients’ assets in a single omnibus account, whether or not such plan is qualified under the Internal Revenue Code of 1986, as amended (the “Code”), and in each case subject to the discretion of the Adviser. The minimum initial investment may be waived for certain investments. For more information, please refer to the section of the Prospectus entitled “Shareholder Information—Minimum Investment Amounts.”

Shares of the Fund may be purchased or sold on any day the New York Stock Exchange (“NYSE”) is open for business directly from the Fund by mail (c/o SS&C Global Investor and Distribution Solutions, Inc., P.O. Box 219804, Kansas City, MO 64121-9804), by telephone (1-800-869-6397) or by contacting an authorized third-party, such as a broker-dealer or other financial intermediary that has entered into a selling agreement with the Fund’s “Distributor,” Morgan Stanley Distribution, Inc. (each, a “Financial Intermediary”). For more information, please refer to the sections of the Prospectus entitled “Shareholder Information—How To Purchase Fund Shares” and “—How To Redeem Fund Shares.”

Tax Information

The Fund intends to make distributions that may be taxed as ordinary income or capital gains, unless you are investing through a tax-deferred arrangement, such as a 401(k) plan or an individual retirement account.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase Class IR shares of the Fund through a Financial Intermediary (such as a bank), the Adviser and/or the Distributor may pay the Financial Intermediary for the sale of Class IR shares and related services. These payments, which may be significant in amount, may create a conflict of interest by influencing the Financial Intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your Financial Intermediary’s web site for more information. For additional information about the Fund’s revenue sharing arrangements for Class IR shares, see the section of the Statement of Additional Information entitled “Revenue Sharing.”

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