Exhibit 99.1

The Blackstone Group Reports First Quarter 2010 Results

Economic Net Income of $360 million for the first quarter of 2010 was up significantly from negative $82 million for the first quarter of 2009.

Net Fee Related Earnings for the first quarter of 2010 were $99 million, up from $90 million for the first quarter of 2009.

Distributable Earnings were $149 million for the first quarter of 2010, up from $77 million in the first quarter of 2009.

GAAP Results Attributable to The Blackstone Group L.P. improved significantly in the first quarter of 2010 with a net loss of $121 million, compared to a net loss of $232 million in the first quarter of 2009, in each case including net IPO and acquisition-related charges.

Fee-Earning Assets Under Management totaled $98.1 billion at March 31, 2010, up from $92.2 billion at March 31, 2009.

Blackstone declares a quarterly distribution of $0.10 per common unit.

New York, April 22, 2010: The Blackstone Group L.P. (NYSE: BX) today reported its first quarter 2010 results.

For the first quarter of 2010, Total Segment Revenues were $711.1 million, up significantly from $45.8 million for the first quarter of 2009. The improvement was driven by increases in Performance Fees and Allocations and Investment Income derived from an increase in the carrying value of the underlying portfolio investments in the Private Equity, Real Estate and Credit and Marketable Alternatives segments. These increases were partially offset by decreased fees earned in the Financial Advisory segment.

Total Segment Expenses were $326.0 million for the first quarter of 2010, an increase from $139.0 million for the first quarter of 2009. The increase in Compensation and Benefits to $253.0 million for the first quarter of 2010 was primarily driven by an increase in carried interest allocations. Base Compensation was $190.6 million for the first quarter of 2010, up from $177.5 million for the first quarter of 2009.

GAAP results for the first quarter of 2010 included Revenues of $701.2 million, compared to $44.9 million for the first quarter of 2009, and Net Loss Attributable to The Blackstone Group L.P. of $121.4 million, compared to a net loss of $231.6 million for the first quarter of 2009.

Equity and credit markets rose in most regions of the world in the first quarter of 2010, although to a lesser extent than in late 2009. In the United States, there is a growing consensus that the risk of a double dip recession has abated which is positively impacting markets. Investor appetite for risk has continued to increase as market participants search for yield in a sustained low interest rate environment. In real estate, the fundamental picture generally improved in the first quarter. In office, occupancy trends and leasing activity improved in certain markets. In hospitality, industry RevPAR (Revenue Per Available Room), an important hospitality industry metric, grew 4% in March, which was the first month of growth in nearly two years.

Stephen A. Schwarzman, Chairman and Chief Executive Officer, said, “We are witnessing a positive trend in most asset classes as the economic recovery takes firmer root and the outlook for growth improves. We are seeing concrete signs of economic improvement in our portfolio, and as a result, the carrying value of investments in Blackstone funds rose meaningfully in the first quarter. During the downturn Blackstone protected investors’ capital and now, as the largest and most diversified independent manager of private investments for public institutions, we are very well positioned to take advantage of opportunities in a reviving world.”

The table below details Blackstone’s Economic Net Income, Net Fee Related Earnings from Operations, Distributable Earnings and Fee-Earning Assets Under Management as of, and for, the first quarters 2010 and 2009. Economic Net Income, Total Segments includes unrealized gains (losses) and the direct compensation impact related to those gains/losses, but excludes IPO and acquisition-related charges.

SEGMENT REVIEW

Private Equity

Private Equity had revenues of $276.8 million for the first quarter of 2010, compared with revenues of $68.1 million for the first quarter of 2009. The change from 2009 was driven principally by combined Performance Fees and Allocations and Investment Income of $175.9 million, which included a $45.7 million realized gain. Compared to the prior year, approximately half of the portfolio companies had growth in revenue and three-fourths had growth in EBITDA, based on their fair market value. The net

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return for Blackstone’s Private Equity funds was 15% in the first quarter of 2010 versus a negative 5% in the first quarter of 2009 and 6% in the fourth quarter of 2009. The improved performance was primarily due to improved prospects for privately held investments reflected in increased operating projections, increased interest from strategic buyers and various balance sheet restructurings. During the first quarter of 2010, the Private Equity funds had realizations from a secondary offering of TRW Automotive of $169.0 million and distributions from certain privately held investments. At March 31, 2010, the unrealized value and cumulative realized proceeds, before carried interest, fees and expenses, of Blackstone’s contributed Private Equity funds represented 1.4 times investors’ original investments. Excluding funds which are still in their Investment Period, the value was 2.2 times investors’ original investments. Blackstone had $1.4 billion of Limited Partner Capital committed to deals made by the Private Equity funds that had not yet closed as of March 31, 2010.

Net Fee Related Earnings from Operations were $28.7 million for the first quarter of 2010, up from $19.9 million for the first quarter of 2009. The change from 2009 was primarily due to a one time fee related to the termination of a monitoring fee arrangement. Economic Net Income was $193.2 million for the first quarter of 2010, up from $53.1 million for the first quarter of 2009, a result of the improved Performance Fees and Allocations and Investment Income (Loss).

Compensation and Benefits expense increased to $59.3 million from $(5.1) million for the first quarter of 2009. The change from 2009 was primarily due to an increase in Performance Fee Related Compensation, driven by improved Performance Fees and Allocations revenue. Other Operating Expenses of $24.4 million were up from $20.1 million for the first quarter of 2009.

Fee-Earning Assets Under Management were down slightly at $25.2 billion compared with $25.5 billion for the first quarter of 2009 reflecting the impact of investment realizations.

Limited Partner Capital Invested during the first quarter of 2010 totaled $387.9 million, including new and follow-on investments, an increase from $196.1 million invested during the first quarter of 2009.

Real Estate

Real Estate had revenues of $152.2 million for the first quarter of 2010, compared with negative revenues of $212.6 million for the first quarter of 2009. The change from 2009 was primarily due to an improvement in Performance Fees and Allocations and Investment Income (Loss), driven by the improved operating performance across investments, modestly reduced capitalization rates and the impact of the acquisition of portfolio company debt. The net return for Blackstone’s Real Estate carry funds was 10% for the first quarter of 2010 compared to a negative 17% in the first quarter of 2009, while the net returns for Real Estate debt investment funds was 9% for the first quarter of 2010 compared to negative 2% in the first quarter of 2009. Blackstone had $562.4 million of Limited Partner Capital committed to deals, or under letter of intent, by the segment’s funds that had not yet closed as of March 31, 2010.

Net Fee Related Earnings from Operations were $29.8 million in the first quarter of 2010, little changed from $30.5 million for the first quarter of 2009. Economic Net Income was $89.3 million for the first quarter of 2010 compared to a negative $187.9 million for the first quarter of 2009, driven by the increases in Performance Fees and Allocations and Investment Income (Loss).

Compensation and Benefits were $48.6 million compared to a negative $37.3 million for the first quarter of 2009. The change from 2009 was primarily due to reversals of prior period carried interest allocations in the first quarter of 2009. Other Operating Expenses of $14.3 million were up from $12.6 million for the first quarter of 2009.

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Fee-Earning Assets Under Management were $23.8 billion compared with $22.9 billion for the first quarter of 2009 reflecting the continued fundraising success of Blackstone’s Real Estate debt platform which grew to $1.7 billion Total Assets Under Management for the quarter.

Limited Partner Capital Invested during the first quarter of 2010 was $424.9 million, up from $215.1 million during the first quarter of 2009.

Credit and Marketable Alternatives (CAMA)

CAMA had revenues of $204.6 million, compared with $99.2 million for the first quarter of 2009. The change from 2009 was due primarily to improved returns, driven by improved performance in equity and credit markets, on the segment’s credit-oriented funds and funds of hedge funds, resulting in positive performance fees and allocations and investment income in both businesses. The net core funds composite returns for Blackstone’s funds of hedge funds was 3% for the first quarter of 2010 compared to 1% for the first quarter of 2009 and 3% for the fourth quarter of 2009. Base management fees also increased as a result of market appreciation in the funds of hedge funds business.

Net Fee Related Earnings from Operations were $34.1 million for the first quarter of 2010, an increase of $19.7 million from $14.4 million for the first quarter of 2009, reflecting increased management fees and general expense reductions. Economic Net Income was $94.4 million for the first quarter of 2010 compared to $14.4 million for the first quarter of 2009.

Compensation and Benefits were $90.6 million, up from $61.1 million for the first quarter of 2009. The increase from the first quarter of 2009 was principally driven by performance fee related compensation due to positive returns on Blackstone’s credit-oriented funds and the funds of hedge funds, partially offset by a decline in base compensation. Other Operating Expenses of $19.6 million were down from $23.6 million for the first quarter of 2009, reflecting a decrease in professional fees and Blackstone’s ongoing focus on expense control.

Fee-Earning Assets Under Management for the first quarter of 2010 totaled $49.1 billion, up from $43.9 billion for the first quarter of 2009. The increase from 2009 was principally due to market appreciation in the funds of hedge funds and closed-end mutual funds.

Limited Partner Capital Invested in certain carry credit-oriented funds during the first quarter of 2010 totaled $157.1 million, down from $208.4 million for the first quarter of 2009.

Financial Advisory

Revenues were $77.5 million for the first quarter of 2010, down from $91.0 million for the first quarter of 2009. The decrease in segment revenues was primarily driven by a decline in fees generated from the restructuring and reorganization advisory services business from the near record revenues achieved in the first quarter of 2009. The decrease was partially offset by increases in fees in the strategic advisory business as several large transactions closed in the quarter. The pipeline for the restructuring and reorganization advisory services business remains strong across a diverse group of industries and geographies. The financial and strategic advisory business is experiencing a cyclical upswing attributable to the improved economic environment and the pipeline for this business continues to be strong and includes a significant international component. The fund placement business saw an increase in fees to more normalized levels as economic conditions negatively impacting institutional allocations to alternative investment funds modestly abated.

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Net Fee Related Earnings from Operations were $6.1 million for the first quarter of 2010, a decrease from $24.7 million for the first quarter of 2009. The primary catalyst for the decrease from 2009 was a decrease in fees generated by Blackstone’s restructuring and reorganization advisory services business related to several large mandates which closed in that period. Economic Net Income was $8.2 million for the first quarter of 2010 compared to $27.1 million for the first quarter of 2009.

CAPITAL AND LIQUIDITY

For Economic Net Income purposes, the weighted-average fully diluted unit count for the first quarters of 2010 and 2009 were 1,126.9 million units and 1,132.2 million units, respectively.

The total number of units used in calculating cash distributions and Distributable Earnings per Adjusted Unit was 1,098.7 million units for the first quarter 2010 and 1,093.4 million units for the first quarter 2009.

As of March 31, 2010, Blackstone had $627.3 million in cash, $703.5 million invested in cash management strategies which included high grade liquid debt strategies and $422.1 million invested in liquid Blackstone funds, against $600 million in borrowings from the 2009 bond issuance. On March 23, 2010, an indirect, wholly-owned subsidiary of Blackstone entered into a $1.07 billion revolving credit facility with a final maturity date of March 23, 2013. Interest on the borrowing is based on an adjusted LIBOR rate or alternate base rate, in each case plus a margin, and undrawn commitments bear a commitment fee.

DISTRIBUTION

The Blackstone Group L.P. has declared a quarterly distribution of $0.10 per common unit to record holders of common units at the close of business on May 14, 2010. This distribution will be paid on May 31, 2010.

For distributions related to fiscal 2010 and thereafter, Blackstone’s current intention is to distribute to its common unitholders substantially all of The Blackstone Group L.P.’s net after-tax share of its annual Distributable Earnings in excess of amounts determined by its general partner to be necessary or appropriate to provide for the conduct of its business, to make appropriate investments in its business and funds, to comply with applicable law, any of its debt instruments or other agreements, or to provide for future distributions to its unitholders for any ensuing quarter. Because Blackstone will not know what its Distributable Earnings will be for any fiscal year until the end of such year, Blackstone expects that its first three quarterly distributions in respect of any given year will be based on its anticipated annualized Net Fee Related Earnings. As such, the distributions for the first three quarters will likely be smaller than the final quarterly distribution in respect of such year. In the fourth quarter Blackstone will distribute the remaining Distributable Earnings for the year, which is expected to also include realized Performance Fees and Allocations net of related compensation and realized net investment income.

In most years the aggregate amounts of Blackstone’s distributions to unitholders will not equal its Distributable Earnings for that year. Distributable Earnings will only be a starting point for the determination of the amount to be distributed to unitholders because as noted above, in determining the amount to be distributed Blackstone will subtract from Distributable Earnings any amounts determined by its general partner to be necessary or appropriate to provide for the conduct of its business, to make appropriate investments in its business and funds, to comply with applicable law, any of its debt instruments or other agreements, or to provide for future distributions to its unitholders for any ensuing quarter.

All of the foregoing is subject to the qualification that the declaration and payment of any distributions are at the sole discretion of Blackstone’s general partner and the general partner may change its distribution policy at any time.

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Because the wholly-owned subsidiaries of The Blackstone Group L.P. must pay taxes and make payments under the tax receivable agreements described in Blackstone’s Annual Report on Form 10-K, the amounts ultimately distributed by The Blackstone Group L.P. to its common unitholders in respect of fiscal 2010 and subsequent years are expected to be different, on a per unit basis, than the amounts distributed by the Blackstone Holdings partnerships to the Blackstone personnel and others who are limited partners of the Blackstone Holdings partnerships in respect of their Blackstone Holdings partnership units.

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Blackstone will host a conference call on April 22, 2010 at 11:00 a.m. ET to discuss first quarter 2010 results. The conference call can be accessed by dialing (888) 680-0892 (U.S. domestic) or +1 (617) 213-4858 (international) pass code 92163618. Additionally, the conference call will be broadcast live over the internet and can be accessed by all interested parties through the Investor Relations section of The Blackstone Group’s website http://ir.blackstone.com. For those unable to listen to the live broadcast, a replay will be available on Blackstone’s website or by dialing (888) 286-8010 (U.S. domestic) or +1 (617) 801-6888 (international) conference ID number 95856654, beginning approximately two hours after the event.

Investor Relations Contacts:

Joan Solotar

The Blackstone Group

Tel: +1 (212) 583-5068

solotar@blackstone.com

Weston Tucker

The Blackstone Group

Tel: +1 (212) 583-5231

tucker@blackstone.com

Media Relations Contact:

Peter Rose

The Blackstone Group

Tel: +1 (212) 583-5871

rose@blackstone.com

About The Blackstone Group

Blackstone is one of the world’s leading investment and advisory firms. We seek to create positive economic impact and long-term value for our investors, the companies we invest in, the companies we advise and the broader global economy. We do this through the commitment of our extraordinary people and flexible capital. Our alternative asset management businesses include the management of private equity funds, real estate funds, funds of hedge funds, credit-oriented funds, collateralized loan obligation vehicles (CLOs) and closed-end mutual funds. The Blackstone Group also provides various financial advisory services, including financial and strategic advisory, restructuring and reorganization advisory and fund placement services. Further information is available at www.blackstone.com.

Forward-Looking Statements

This release may contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934 which reflect Blackstone’s current views with respect to, among other things, Blackstone’s operations and financial performance. You can identify these forward-looking statements by the use of words such as “outlook,” “believes,” “expects,” “potential,” “continues,” “may,” “will,” “should,” “seeks,” “approximately,” “predicts,” “intends,”

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“plans,” “estimates,” “anticipates” or the negative version of these words or other comparable words. Such forward-looking statements are subject to various risks and uncertainties. Accordingly, there are or will be important factors that could cause actual outcomes or results to differ materially from those indicated in these statements. Blackstone believes these factors include but are not limited to those described under the section entitled “Risk Factors” in its Annual Report on Form 10-K for the fiscal year ended December 31, 2009, as such factors may be updated from time to time in its periodic filings with the SEC, which are accessible on the SEC’s website at www.sec.gov. These factors should not be construed as exhaustive and should be read in conjunction with the other cautionary statements that are included in this release and in the prospectus. Blackstone undertakes no obligation to publicly update or review any forward-looking statement, whether as a result of new information, future developments or otherwise.

This release does not constitute an offer of any Blackstone Fund.

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THE BLACKSTONE GROUP L.P.

Exhibit 1. Consolidated Statements of Operations

(Dollars in Thousands, Except Per Unit Data)

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THE BLACKSTONE GROUP L.P.

Exhibit 2a. Economic Net Income and Net Fee Related Earnings from Operations

(Dollars in Thousands)

The tables below detail Blackstone’s Economic Net Income and Net Fee Related Earnings from Operations. Net Fee Related Earnings from Operations is a supplemental measure of after tax performance used to highlight earnings from operations excluding the income from and related profit sharing expenses of Blackstone’s performance fees and allocations and investment income, except for interest income. The reconciliation of Economic Net Income to Net Fee Related Earnings from Operations is presented in Exhibit 2b to this release.

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THE BLACKSTONE GROUP L.P.

Exhibit 2a. Economic Net Income and Net Fee Related Earnings from Operations - Continued

(Dollars in Thousands)

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THE BLACKSTONE GROUP L.P.

Exhibit 2a. Economic Net Income and Net Fee Related Earnings from Operations - Continued

(Dollars in Thousands)

continued…

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THE BLACKSTONE GROUP L.P.

Exhibit 2a. Economic Net Income and Net Fee Related Earnings from Operations - Continued

(Dollars in Thousands)

continued…

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THE BLACKSTONE GROUP L.P.

Exhibit 2a. Economic Net Income and Net Fee Related Earnings from Operations - Continued

(Dollars in Thousands)