The Tesla CEO and Twitter owner had held the position on Forbes’ rich list since September 2021, after his wealth overtook Amazon founder Jeff Bezos.
According to the Bloomberg Billionaires Index the 51-year-old is estimated to have lost about $US100 billion ($145 billion) since January.
That’s allowed Arnault, chief executive of luxury brand Louis Vuitton’s parent company LVMH, to emerge triumphant.
The 73-year-old’s wealth, derived from a 48 per cent ownership stake, sits around $US170.6 billion ($248.91 billion).
Arnault’s luxury brands cater to the affluent, and include Christian Dior, Fendi, Bulgari and Tiffany, as well as champagne house Moet & Chandon.
Musk’s unseating comes days after a controversial tweet in which he called for the prosecution of top US health official Anthony Fauci, went viral.
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His call has sparked condemnation around the world with the White House and former Deputy Chief Medical Officer Nick Coatsworth both condemning the tweet.
According to a forecast by market research agency Insider Intelligence more than 30 million users are expected to leave Twitter over the next two years.
It comes as Tesla’s fortunes spiral.
The electric car maker’s stock has dropped by 56 per cent in the last year, down to its lowest point since November 2020, as it feels the impact of COVID-19 restrictions and a weakening economy in China.
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