Russian gas giant Gazprom was the world's most profitable company in 2009 despite ranking 50th in revenue, Fortune magazine said on Thursday with the publication of the Fortune Global 500.

U.S.-based retailer Wal-Mart Stores Inc was ranked No. 1 by revenue.

Gazprom's net income fell 17.8 percent to $24.56 billion in 2009, but its standing improved because profits from oil majors that had been ranked higher fell more than 50 percent due to the correction from 2008's historically high crude prices.

That left a company that is 49 percent-owned by the Russian government as the world's most profitable by Fortune's measure, moving up from the No. 2 spot to break a five-year run by Exxon Mobil in the No. 1 position.

Wal-Mart regained the No. 1 spot by revenue for 2009, leaping over oil companies Royal Dutch Shell and Exxon, which ranked one and two in 2008.

Wal-Mart has held the top ranking in revenue in seven of the past 10 years but fell to third in 2008. The full list is posted on www.fortune.com.

Wal-Mart revenue rose 0.6 percent to $408 billion in 2009, while revenue for Shell and Exxon fell 40 percent and 36 percent, respectively, to about $285 billion for both companies.

China's presence on the list grew to 46 companies, nine more than in 2008, putting China third behind the United States and Japan.

Revenues for all 500 companies fell 8.3 percent to $23.1 trillion, while profits rose 16.9 percent to $960.5 billion.

The 500 companies employed 57.9 million people, up 2.3 percent from 2008. Eleven of the 500 CEOs were women.

(Reporting by Daniel Trotta; Editing by John Wallace)