It happened around 9 p.m. on the 5300 block of Greenway Avenue.
Police say a 19-year-old man was shot once in the stomach. He was rushed to an area hospital where he's listed in critical condition.
Two additional 19-year-olds are in stable condition after being shot, said police.
Two weapons were recovered, but no arrests have been made.
Anyone with any information is asked to call police at 215-686-TIPS.