The robbery happened on December 21.
Surveillance shows the thieves walking into Papi's Grocery store on the 6100 block of Baynton Street around 4:30 p.m.
One suspect points a handgun at the clerk before jumping over the counter.
The trio got away with $2,300 in cash, two cell phones and cigarettes before fleeing the scene.
They were last spotted driving away in an unknown vehicle on Baynton Street towards Tulpehocken Street.
Police describe the first suspect as a black male, 6'0 tall with an athletic build, light complexion and big eyes. He was wearing a gray hooded sweatshirt with thick white draw strings, black pants, black knit hat, white sneakers with a black stripe, red underwear, light colored scarf covering his face, black rubber gloves and armed with a handgun.
The second suspect is described as a back male, 5'10 tall with a thick build and dark complexion. He was wearing a white/turquoise hooded sweatshirt, black pants, red underwear, black sneakers with a white "Nike" logo, white scarf covering his face and armed with a handgun.
The third suspect is described as a black male, 5'6-5'7 tall with a thin build and dark complexion. He was wearing a black hooded sweatshirt pulled to the top of his head, black pants, black/red sneakers with white soles.
Anyone with information is asked to contact Philadelphia Police at 215.686.TIPS (8477) or text a tip to PPD TIP (773847).
All tips will remain confidential.
VIDEO: Click here to watch the surveillance video