ACTOR David Duchovny, star of TV shows Californication and The X Files, has checked into rehab for treatment for his sex addiction.

In a statement from his lawyer Stanton Stein, the actor said he did so voluntarily, the Associated Press reported.

"I ask for respect and privacy for my wife and children as we deal with this situation as a family," Duchovny said.

Duchovny, 48, plays a sex-obsessed character on the TV series Californication, which earned Emmy nominations for casting and cinematography.

The show's second season begins in the US next month.

The actor has been married to actress Tea Leoni since 1997. They have two children.