The incident took place on the 4300 block of Edgemont Street in the city's Bridesburg section around 8:15 p.m.
Police and medics were called to the scene for the report of an unresponsive boy in a residential swimming pool.
Both agencies arrived and immediately attempted to resuscitate the boy.
Medics rushed the lifeless boy to St. Christopher's Hospital for Children where he was pronounced dead a short time later.
15th District police and Northeast Detectives are conducting the investigation.
There is no word on who was with the boy at the time of the accident.