"I have voluntarily entered a facility for the treatment of sex addiction. I ask for respect and privacy for my wife and children as we deal with this situation as a family," US Weekly quoted Duchovny, as saying in a statement.
In the year 1997, the actor, who is presently married to actress Tea Leoni with two children, had denied all reports that he's a sex addict.
"I'm single and I had a long-term girlfriend up until last November, I have been seen with more than one woman in the last few months, so I'm an easy target for those kind of things," the actor told Playgirl magazine.
"I'm not a sex addict, I have never been to those meetings, it's hurtful to my family and if I was involved with a woman in a monogamous relationship, it would be hurtful to her, There was another story claiming I was a neat freak.
"If I had to choose one of the two, I think I'd rather be a sex addict, It's not funny and I'll be glad when it goes away," he had added.