It happened on August 9 inside the Ba Le Bakery on the 600 block of Washington Avenue.
The woman was caught on surveillance taking a cell phone that was left behind on the counter by a previous customer.
She can be seen hiding it under some merchandise and slipping it into her purse.
Anyone with information should call police at 215.686.TIPS (8477) or text a tip to PPD TIP (773847).
Click here to watch the surveillance video