Amazon said its net income declined to $197 million in the second quarter, from $857 million the same period last year, marking a massive 77 percent decline.
Revenue rose 25 percent to $38 billion from $30.4 billion, but that was not enough for Bezos to retain his title.
The e-commerce giant stock price plunged 3.2 percent to as low as $1,020 per share in after-hours trading, after they closed the day at $1,046 a share.
Bezos, who owns 17 percent of Amazon stocks, saw his net worth falling to $88.7 billion, according to Forbes’ World’s Billionaires Real Time Ranking.
Microsoft co-founder Bill Gates regained his title of world’s richest person with $89.8 billion of net worth, the ranking showed.
Amazon is still the world’s fourth biggest firm by market capitalisation behind Microsoft, while Facebook is closing on the e-commerce giant.
In fact, Facebook may surpass Amazon in market value if the latter’s shares continue to decline on Friday due to weak earnings, according to analysts.