The 32-year-old victim sustained a graze wound to the head and was transported to a hospital, police said.
At about 9 p.m., officers from the 8th District saw individuals drinking in a park near West 56th Street and South Artesian Avenue. They saw one man with a gun and during a confrontation with the man, an officer fired.
A weapon was recovered from the scene, police said. The officer involved in the shooting will be placed on administrative duties for 30 days.
The Independent Police Review Authority is investigating.