The shooting was reported at about 7 p.m. near Fillmore and McAllister streets.
The victims, a 20-year-old man and two teens, were taken to San Francisco General Hospital to be treated for gunshot wounds to their legs and feet, police spokesman Officer Gordon Shyy said. Their wounds are not considered life-threatening.
Police are seeking a gray, older-model sports car believed to have been involved in the shooting, Shyy said.
Anyone with information about the case is encouraged to call the Police Department's anonymous tip line at (415) 575-4444 or send a tip by text message to TIP411 with "SFPD" in the message.