It happened on January 9 on the 6100 block of Woodland Avenue.
Police say the suspect walked by the Empress Designs Clothing Store at 4:35 p.m.
As he walked past the store, he grabbed several pairs of socks from a display table outside without paying and continued walking away.
The store owner ran to confront the suspect and that's when he turned around and pointed a gun.
He threatened the employee and told him not to follow him before fleeing west on Yocum Street.
Police describe the suspect as a black male, 35 years-old, 6'1" tall with a light complexion, medium build and light facial hair. He was wearing a green jacket, dark colored jeans and a black fur lined hat.
If you recognize this suspect, call police at 215.686.TIPS (8477) or text a tip to PPD TIP (773847).
VIDEO: Click here to watch the surveillance video