Jim Carrey Rebounding with Hot NEW Piece of Ass

9/17/2012 6:17 AM PDT
Jim Carey and his new girlfriend?Call him Ass Ventura.

Jim Carrey hit the beach in Malibu this weekend with a brand new thongtastic bikini chick ... just a short time after reportedly breaking things off with his last GF -- 23-year-old Anastasia Vitkina.

50-year-old Carrey is a LEGEND on the Hollywood dating scene ... cycling through stunners like Jenny McCarthy, January Jones, Renee Zellweger and Lauren Holly.

0917_jim_carrey_girlfriend_subasset_fameSo far, the identity of the new chick with the great butt is unclear ... but we're hoping this one sticks around a while.