It happened at the Family Dollar Store located on the 100 block of West Chelten Avenue.
The suspect was caught on surveillance video walking into the store at 10:45 a.m. and browsing around.
After several minutes, he walked behind the counter and helped himself to several packs of cigarettes.
When an employee tried to stop him at the front door, the robber fought back and threw the clerk to the ground.
He ran from the store with $30 worth of cigarettes in hand.
The employee suffered only minor injuries.
Police describe the suspect as a black male in his 30s, 6'5" tall with a medium build and dark complexion. He had a scruffy beard and was wearing a black thick jacket, striped knit hat, gray jeans and dark sneakers.
If you recognize this man, call police at 215.686.TIPS (8477) or text a tip to PPD TIP (773847).
All tips will remain confidential.