Several cars were moving on Harbor Boulevard when 56-year-old Kelly Jay Henningsgaard walked into the southbound lanes midblock. Authorities said he died at the scene.
The coroner's office said Henningsgaard had no known place of residence.
If you have any information regarding this crash, you're urged to call the Fountain Valley Police Department's Traffic Bureau at (714) 593-4481.
City News Service contributed to this report.