The accident happened just before 3 a.m. as an officer was driving a marked patrol car east on Alum Rock Avenue.
Officer Jermaine Thomas said the pedestrian, a 44-year-old man, "walked out into the street mid-bock" between 34th Street and South King Road.
The man was struck by the patrol car, which was not responding to a call at the time and was traveling at the speed limit, Thomas said. The speed limit in that area is 35 mph.
The pedestrian was taken to a hospital with injuries that did not appear to be life-threatening, Thomas said. The officer was not injured.
The patrol car sustained "minor to moderate" damage, Thomas said.
There is no crosswalk at the spot where the man was hit. The collision remains under investigation but alcohol may have been a factor, Thomas said.
"There was an odor of alcohol on the pedestrian," he said.