It happened on January 17 inside the Ace Check Cashing store located on the 5000 block of North Wayne Avenue.
Police say the suspect walked into the store at 9:15 a.m. and approached the glass booth.
He pointed a handgun at the employee and demanded to open the door and go behind the counter.
The clerk hit the silent robbery alarm and hid inside the bathroom until the police arrived.
VIDEO: Click here to watch the surveillance video
The suspect fled on foot down Wayne Avenue towards Manheim Street.
Nothing was taken during this incident.
The suspect is described by police as a black male, 40-50 years-old with a dark complexion, beard and stocky build. He was wearing a black hooded puffy coat, purple hooded sweatshirt, blue baseball cap with white on the front, and black/white sneakers.
If you recognize this suspect, call police at 215.686.TIPS (8477) or text a tip to PPD TIP (773847).
Tips will remain confidential.