The Knight Rider actor hosted the celebrations at the Greystone Manor Supperclub in Los Angeles with his 32-year-old girlfriend Hayley Roberts.
The pair posed for pictures as they arrived outside the club, which was also attended by Mel B among others.
Hasselhoff had earlier tweeted: "Hoff the charts tonight @Greystone_Manor Celebrating the big 60! Cant wait to see all my baywatch and knight rider friends! (sic)".
He added: "On my way to Greystone Manor to party Hoff style see ya there !!! Thanks to all for coming!!"
The actor recently confirmed that he will star in an upcoming movie version of Baywatch.
He said: "I've just met the guy writing the film. I'm going to play myself.
"We're trying to make it a very cool, updated version."