Hugh Hefner has been DUMPED. He was supposed to marry 25-year-old Crystal Harris on Saturday, but yesterday, she called off the wedding.

Hugh (who's 85) Tweeted, quote, "The wedding is off. Crystal has had a change of heart."

TMZ is reporting that Crystal decided to move out and cancel the wedding after she and Hugh had a nasty argument over the weekend. There's no word what it was about.

Hugh and Crystal had been dating since January of 2009, and got engaged this past Christmas.

Talk about timing! Crystal recently filmed a video for FunnyOrDie.com. You can watch it here: