The shooting was reported shortly after 6 p.m. in the parking lot of Stadium Promenade, a popular entertainment complex packed with people, located in the 1500 block of W. Katella Avenue.
A man was found suffering from a gunshot wound in the parking lot between Chili's and the Cinemark Century Stadium movie theater.
The victim was transported to a nearby hospital, where he died.
The search for the shooter was underway. Witnesses said the suspect was last spotted speeding off in a white pickup truck fleeing north on Main Street.
Anyone with information is encouraged to call the Orange Police Department at 714-744-7444.