Bill Gates, cofounder of Microsoft, has reclaimed his title as the world’s richest man.

Forbes magazine said Gates topped its list of billionaires for 2009, having a total net worth of 40 billion dollars.

Warren Buffet, chairman of Berkshire Hathaway Incorporated, slipped one position to number two, after seeing a plunge in his company's shares following the global economic crisis.

The magazine says there are a total of 739 billionaires worldwide this year, down 332 from last year. Their average net worth also fell by 23 percent to about three billion dollars.

The magazine listed four Koreans as billionaires --- including former Samsung Group Chairman Lee Kun-hee, Hyundai-Kia Motor Group Chairman Chung Mong-koo, lawmaker Chung Mong-joon and Shinsegae Chairwoman Lee Myung-hee.