The incident happened around 11:00 a.m. at the Check N' Go store, located in the unit block of Chestnut Hill Plaza.
Police say a man armed with an unknown type of hand gun, entered the store and demanded money.
The employee handed over an unknown amount of cash and the man fled on foot.
The suspect is described as a white male, wearing a mask and all dark clothing.
Police say, no one was injured and they are investigating.