The incident happened around 9 p.m. Wednesday near Edinger and Grand avenues in Santa Ana.
Officials said Juan Manuel Diaz, 36, and a passenger were driving along the 1600 block of Edinger Avenue in a black van when someone shot at them.
Diaz was struck and lost control of the van. He started driving the wrong way and plowed into a Volkswagen Beetle that was carrying a family of five.
"We heard five or six gunshots right in a row," said witness Mark Frei.
Frei said seconds later he heard the sound of the car crash.
An aunt, uncle and their two young nieces and a nephew were hurt. All five family members were treated at UC Irvine Medical Center with non-life-threatening injuries.
Diaz died at the scene. The 23-year-old passenger in his van also was shot, and is reportedly doing OK.
Authorities said they believe the shooting was gang-related.
The shooter remains at large. The suspect vehicle was described as a dark-colored SUV.
Anyone with information was asked to contact Santa Ana police at (714) 245-8400.