Matthew Oropeza, 24, surrendered at Philadelphia Police Department headquarters Thursday.
Authorities say 38-year-old Drew Justice and his fiancee were walking their dog in Gold Star Park at Sixth and Wharton streets Saturday night when he asked Oropeza to leash his dog.
Police say that sparked an argument, which ended when Oropeza punched Justice, who fell backward, slamming his head on the ground.
READ: Dog leash dispute turns deadly at South Philly park
Authorities say Oropeza then ran off. Justice was pronounced dead a short time later.
Police had been looking for Oropeza since Saturday night.
In addition to involuntary manslaughter, Oropeza is charged with simple assault, reckless endangerment and terroristic threats.