It happened inside Roy's Lounge and Seafood located along the 1900 block of West Hunting Park Avenue early Tuesday morning.
A 47-year-old worker told investigators the suspects walked in with guns drawn and announced a robbery.
The masked men took the victim's cell phone and $300-$400 in cash and ran.
The worker's cell phone was later found by police at Ruffner and Pulaski Avenue.
She was not hurt.
If you have any information about this crime or these suspects, please contact: Northwest Detective Division at (215) 686-3353.