It happened at the Family Dollar Store located on the 6200 block of North Front Street around 2:30 p.m.
Police say the masked robber entered the store, pointed a handgun at the cashier and demanded cash from the register.
He got away with $60 before fleeing the scene.
The suspect is described as a black male, 18-22 years-old, 5'9-6'0" tall with a medium complexion and thin build. He was wearing a black wool mask, brown coat with a fur lined hood, black pants, and black boots.
Anyone with information on this theft should call police at 215.686.TIPS (8477) or text a tip to PPD TIP (773847).
VIDEO: Click here to see the surveillance video