Mark Zuckerberg is now richer than Google co-founders Sergey Brin and Larry Page.
The Facebook chairman added $US1.6 billion ($1.7 billion) to his fortune as the world's biggest social network ended last week at a record high.
The surge elevated the 30-year-old's net worth to $US33.3 billion, moving him past Mr Brin, 40, and Mr Page, 41, as well as Amazon.com chief executive Jeff Bezos, 50, on the Bloomberg Billionaires Index.
Mr Zuckerberg is No. 16 on the ranking. The Google founders are 17th and 18th. Mr Bezos occupies the 20th spot.
"He's just getting started," David Kirkpatrick, author of The Facebook Effect, said.
"He's going to become the richest person on the planet."
On Thursday, Facebook exceeded expectations by posting second-quarter sales that soared 61 per cent to $US2.91 billion. Net profit for the period more than doubled to $US791 million.
Facebook shares have jumped 183 per cent in the past 12 months, the biggest rally in the Standard & Poor's 500 Index. It trades at 82 times reported earnings, compared with 18.2 for the S&P 500.
The group accounted for 5.8 per cent of worldwide digital ad revenue in 2013, up from 4.1 per cent in 2012.
Its performance also expanded the fortunes of other Facebook shareholders. Those include Dustin Moskovitz, the 30-year-old who started the social network with Mr Zuckerberg at Harvard University, and Sheryl Sandberg, Facebook's 44-year-old chief operating officer, who became one of the world's youngest female billionaires in January.
Ms Sandberg owns shares valued at $US740 million and has collected more than $US550 million in share sales.
Tucker Bounds, a spokesman for Facebook, didn't respond to an email seeking comment.
Bill Gates remains the world's richest person with an $US84.7 billion fortune. The Microsoft chairman's net worth has grown 7.9 per cent this year, with five of his biggest shareholdings, including Microsoft, Canadian National Railway and Republic Services, accounting for almost $US4 billion of the gain.
Mr Gates, who controls most of his fortune through holding company Cascade Investment, collected about $US400 million in dividends this year.
Mexican telecommunications tycoon Carlos Slim has a $US78.8 billion fortune.