It happened outside LJ's Cafe on the 2900 block of Frankford Avenue just before 2 a.m.
Police say the suspect approached a 29 year-old man inside the cafe to sell him some DVD's.
After the victim made a purchase, the suspect followed him outside.
He can be seen confronting the man on the street before pointing a gun at him and demanding cash.
The robber then knocked the man to the ground and went through his pockets.
He got away with nearly $120 in cash and the man's cell phone before fleeing on foot.
Police describe the suspect as a black male, 20 years-old with a thin build, light chin hair and acne. He was wearing a black hooded sweatshirt with lettering , black pants, and armed with a handgun.
If you see this suspect do not approach him, contact 911 immediately.
Anyone with information on this robbery should call police at 215.686.TIPS (8477) or text a tip to PPD TIP (773847).