A sneaky thief was caught on surveillance camera brazenly grabbing a woman’s wallet out of her purse while sitting next to the unsuspecting victim, who was trying on knee-high boots in a Rego Park store at the time, police said today.

The 39-year-old victim had placed her handbag beside her as she sat down, took off her shoes and tried on a pair of black leather boots inside Century 21 around 11:30 a.m., Jan. 20, cops said.

The pudgy perp plopped herself down beside the shopper and stealthily reached around her back several times to try to get the wallet, before finally successfully plucking it from the victim’s pocketbook, cops said.

The suspect is believed to be in her 40s, about 5-foot-4 and heavyset with long black hair. She was wearing a black coat and black pants.