It happened around 10:30 a.m. Thursday in the area of St. Chris Drive in the city's Hunting Park section.
Officials say police arrived to find a man armed with a gun and an officer discharged, striking the man.
The victim was transported to an area hospital where he was pronounced dead.
It's unclear why the man was armed or if he attempted to fire at police first.
Chopper 6 was overhead shortly after the shooting, where a gun could be seen on the ground near some bushes.
Police say they believe the man was suffering some kind of mental health issue.
A woman who was standing next to the man was taken to Temple University Hospital in critical condition, though it's not yet clear how she was hurt.
It's not yet known if either the man or the woman had any connection to the hospital.
The shooting remains under investigation.