A Williamsburg resident is celebrating Xmas with a very X rated decoration.

He hung Christmas lights in the shape of a penis out of his fifth floor window on 65 Ainslie Street – leaving some passersby laughing and others outraged.

“It’s juvenile, but I’m surprised folks are having an issue with it because it’s this kind of neighborhood,’’ said a woman named Charee who used to live nearby.

“It can be considered art,’’ said Patricia Wright of Greenpoint. “Americans are a little too puritanical.’’

But a worker in the building said, “It’s not good for the kids.’’