The incident happened Tuesday around 10:45 p.m. along the 1300 block of Locust Street.
Click here to watch the surveillance video
Police say the suspect asked the 69-year-old male victim for some money.
When the man opened up his wallet to give $1, the robber pushed him to the ground and stole his wallet.
The victim suffered a cut lip and a lump on his head from the fall, but was otherwise ok.
Police describe the suspect as a white male, 30-years-old, 5'10 tall and 160lbs. with blue eyes and short brown hair. He was wearing a brown shirt, and gray sweatpants.
Anyone with information is asked to call police at 215.686.TIPS (8477) or text a tip to PPD TIP (773847).