The masked robber entered the La Villa Hermosa Market at 4511 El Cajon Boulevard at 6:50 p.m., Saturday and pointed a gun at the clerk and demanded money, according to San Diego police.
The clerk gave the suspect an undisclosed amount of cash.
According to police, the gunman left the store and fled the scene on a blue bicycle.
Police described the suspect as a white male in his 30s.
No injuries were reported.
Anyone with information is asked to contact San Diego Police at 619-531-2204.