Passing joggers discovered the body about 5 p.m. Monday near the intersection of Merion and Narberth avenues.
It took firefighters and police several hours to remove the body from the marsh-like terrain of Pennypacker Park.
Detectives told Action News it appears the man had been dead for a couple of days. Advanced decomposition made it difficult for investigators to see obvious signs of trauma, though they believe the victim was targeted.
Investigators are hopeful the victim's tattoos will help them identify him.