A one-alarm fire at 2211 N. Main St. was reported at 4:30 a.m., a Contra Costa County Fire Protection District dispatcher said. The fire was under control by 6:30 a.m.
No injuries were reported at the vacant building, the dispatcher said.
Police shut down part of North Main Street and North California Boulevard for about three hours until 10:30 a.m. once fire crews had left, police said.
The fire broke out at the former site of the restaurant La Virage. A dispatcher said the fire caused about $500,000 in damage.
The cause of the blaze is under investigation.