Including Thursday’s gains in Tesla shares, Musk, 49, had a net worth of more than US$188.5 billion, US$1.5 billion more than Bezos, the report said.
Musk’s personal wealth has been boosted by last year’s more than eight-fold surge in the shares of Tesla, which became the world’s most valuable carmaker.
He has a 20-per-cent stake in the carmaker and about US$42 billion of unrealized paper gains on vested stock options, according to the Bloomberg report.
Tesla shares were up as much as 7.4 per cent on Thursday at a record high of US$811.61.
The Forbes Billionaires List, however, said Musk still trails Amazon’s Bezos by US$7.8 billion.
Forbes has a more conservative estimate based on the Tesla stake that he has pledged as a collateral for personal loans. To take that into account, it applies a 25-per-cent discount to his shareholding, according to its report in November.
Musk, who co-founded and sold Internet payments company PayPal Holdings Inc, now leads some of the most futuristic companies in the world.
Besides Tesla, he heads rocket company SpaceX and Neuralink, a startup that is developing ultra-high bandwidth brain-machine interfaces to connect the human brain to computers.
He set up the Boring Company to make affordable tunnels below busy city streets for an all-electric public transportation system to avoid the nasty traffic jams in U.S. cities.
(Reporting by Akanksha Rana in Bengaluru; Editing by Arun Koyyur)