Officers responding to a large crowd and disturbance in the 2100 block of Wharton Street around 10:30 p.m. on Wednesday heard the gunshots.
When they arrived on the scene, officers found a man lying on the street with gunshot wounds to the head and leg.
The victim, who lives nearby, has been identified as 31-year-old Walter S. Holloway, according to police.
He died at the hospital.
Police say the gunman ran away.
"We are getting some information that these two individuals - the shooter and the victim -- may have been involved in a previous altercation as recently as yesterday, and may have escalated into the shooting today," said Chief Inspector Scott Small, with the Philadelphia Police Department.
Police are searching surveillance video as they look for the killer.
Anyone with information regarding this incident is asked to contact the Homicide Unit at 215-686-3334 or submit an anonymous tip at 215-686-TIPS.