Authorities responded to numerous calls reporting gunshots near the 1300 block of Tullibee Road at around 11:05 p.m., Contra Costa County sheriff Lt. George Wright said.
Officers arriving in the area found a male victim struck by gunfire lying in the street, Wright said.
The victim was pronounced dead at the scene.
A home and a vehicle in the area had also been hit by bullets, Wright said, though no other injuries were reported.
Investigators had not determined if the fatal gunfire came from a passing vehicle or another source, Wright said.
Witnesses were believed to have been in the area at the time of the homicide, and the sheriff's office this morning urged anyone with information to contact investigators at (925) 646-2441.