MTV funnyman Tom Green stopped the laughter last night as he revealed that he has cancer.

The 28-year-old comic told “Entertainment Tonight” that he’s undergoing surgery at an undisclosed hospital, and added that the prognosis for a full recovery is good.

Green is best known for pulling wild pranks on his late-night show — and there were some doubts about whether the cancer scare was a joke.

“As far as we can tell, this is very, very real. It’s quite a jolt,” one producer at MTV said.

Green was taping an interview with “ET” last night in which he’ll reveal the type of cancer he has. It’ll be aired tonight at 7 on WCBS/Channel 2.

The entertainer is taking a break from his program, “The Tom Green Show,” during his treatment.

His doctors say the cancer is curable and that he should be back to work in a few months, “ET” said.