The shooting was reported at 8:17 p.m. in the 800 block of Webster Street.
The victim, a 32-year-old man, was struck in the right side of his lower back when the gunfire came into the home, police spokesman Officer Carlos Manfredi said.
He was taken to San Francisco General Hospital to be treated for his injuries, which are not considered life-threatening, Manfredi said.
A green coupe was seen leaving the area following the shooting, but no other suspect information was immediately available today, Manfredi 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.