The shooting happened just before midnight Sunday at Luma Hotel in the 100 block of Channel Street, not far from Oracle Park and Chase Center.
Officers found the victim, who was transported him to the hospital with life-threatening injuries.
He's been identified as a 28-year-old man from Ohio who arrived at the Luma Hotel after a wedding reception.
When crews arrived, there were windows shattered at the hotel. One witness told ABC7 News he heard up to seven shots.
Police say no arrests have been made in the shooting.
Anyone with information is asked to contact the SFPD at 415-575-4444 or text a tip to TIP411 and begin the message with SFPD. You may remain anonymous.