California Jam II (also known as Cal Jam II) was a music festival held in Ontario, California, at the Ontario Motor Speedway on March 18, 1978, and produced by Leonard Stogel, Sandy Feldman, and Don Branker. More than 350,000 people attended. The event was promoted by Wolf & Rissmiller Concerts. The festival was a sequel to the original California Jam held in 1974.