It happened around 10 p.m. at Ed's Pizza located on the 5300 block of Rising Sun Avenue.
Police said a man with a yellow mask held up several customers at gunpoint, stealing their wallets before driving away in a black Lexus.
The owner of the business said approximately $500 was also taken from the register.
Pizza shop customers robbed at gunpoint in Olney
Officials said no shots were fired and no one was injured in the incident.
Anyone with information is asked to contact the police.