The Biden Administration is poised to announce a new tax on the wealthy that could send Elon Musk into orbit.

Biden’s “Billionaire Minimum Income Tax” proposal would set a 20 percent tax rate floor on Americans worth more than $100 million — hitting not only their stated income, but also their unrealized gains on stock holdings and other forms of wealth.

The plan will be included in the budget proposal that the White House will roll out Monday, the Washington Post reported.

Musk attacked a version of the plan in October, when it was being considered as way to help pay for Biden’s since-abandoned “Build Back Better” social spending bill.

“Eventually, they run out of other people’s money and then they come for you,” the multi-billionaire Tesla CEO and SpaceX founder posted on Twitter last year.

Biden’s new tax could raise up to $360 billion over 10 years, say the aides who developed it, and would fall on the richest 700 Americans.

That would include Musk — as well as major Biden supporters like Amazon’s Jeff Bezos and Facebook’s Mark Zuckerberg.

In December, Musk said that the 2021 tax bill on his estimated $243 billion fortune totaled $11 billion.

But the levy, which would have to be passed by Congress, could face headwinds even in Biden’s own party.

Democrats such as House Speaker Nancy Pelosi and West Virginia Sen. Joe Manchin have expressed firm opposition to previous versions of the plan, calling it a publicity stunt unlikely to pass Congress.