The crash happened a little before 8:15 a.m. Thursday at Mosside Boulevard and Hillside Avenue.
Allegheny County police said one of the drivers was taken to the hospital, where he died.
The medical examiner’s office identified the victim as James Adams, 77, of West Mifflin.
The other driver was not hurt, police said.
County homicide detectives are investigating the cause of the crash. Anyone with information is asked to call police at 833-ALL-TIPS.