The robbery was reported about 1:30 a.m. at the Gas & Shop station at 599 S. Van Ness Ave., according to police.
The suspect entered the station’s store, pulled out a gun and demanded money. He then picked up the entire cash register and ran off, police said.
The suspect had not been found as of Wednesday evening.
Anyone with information about the robbery is asked to call the Police Department’s anonymous tip line at (415) 575-4444 or send a tip by text message to TIP411 with “SFPD” at the beginning.