It happened at 6:38pm Sunday in the 2600 block of South 7th Street.
Lawmen say the suspect entered the Double-O-Seven Store, pointed a handgun at the clerk and demanded money from the cash register.
RELATED: Watch the surveillance video.
The clerk complied and the suspect made off with $225 in cash. He fled the store running north on 7th Street.
Authorities are looking for white man, about 30 years old, 6 feet 2 inches tall with blond hair, blue eyes and wearing a gray hoodie, blue jeans and black cloth across his face.
Anyone with information about this crime or this suspect is asked to contact
Philadelphia Police
South Detective Division
215-686-3013 or -3014