Losing — at the box office!

Charlie Sheen’s roller-coaster ride plunged downward yesterday after he bombed Friday night at Radio City Music Hall.

Online ticket sales for Sheen’s show tonight tanked in the hours after he was heckled off the famed Rockefeller Center stage.

Chuckling Charlie performed well-received shows in Ohio on Tuesday and Wednesday, and the average StubHub price for tonight’s show spiked Wednesday to $104 apiece, according to a company spokeswoman.

But yesterday, as word of his awful Friday night performance spread, the average price plummeted to $61 a ticket.

Last night, Sheen performed in Wallingford, Conn., to better results, according to TMZ.com — which reported that the unemployed actor managed to get through an entire show without boos and that the jubilant crowd walked out chanting, “F- -k NYC!”