According to TMZ, the actor owes the US government almost $500,000 (£325,650) in unpaid federal taxes.
The IRS has now put a lien on Kilmer in New Mexico. He is reportedly looking to sell his 6,000-acre ranch in the state.
Kilmer settled a previous debt with the IRS for $538,000 (£350,399) earlier this month.
The MacGruber star has yet to comment on the news.