Tia Carrere -- Dancing With a Purse Thief

Tia Carrere's dance moves didn't do her any good last night when she encountered a purse thief in her Las Vegas dressing room following a performance of "Dancing With the Stars: Live in Las Vegas" last night ... TMZ has learned.

According to our sources, Carrere came face-to-face with a guy lurking in her private dressing room after her 10:00 PM show at the Tropicana last night. Rather than scream for help, Carrere tried to give the guy the benefit of the doubt and see what he was doing there ... but he promptly bolted right past her.

Carrere then called out for help, but it was too late ... our sources say the guy made off with her purse, two iPhones, and a wad of cash. We're told another dancer, Anya Garris, had her wallet cleaned out as well.