The woman said her grandson dropped her off at the store at 709 Lincoln Road West in Vallejo at about 12:30 p.m. on Sept. 30 shortly after she had cashed a check, Sgt. Kenny Park said.
The woman said she put her purse in the child seat of her shopping cart, momentarily turned her back and then noticed it was missing, Park said.
Store surveillance video shows a man pushing a shopping cart past the woman and grabbing her purse.
The suspect is a white man possibly in his 30s or early 40s with dark hair, a receding hairline, a mustache and goatee. He was wearing a white T-shirt, blue jeans and white shoes.