The buyback was held on Howard Street in the South of Market area, where police collected handguns, shotguns, high-powered rifles, and even an AT4 anti-tank weapon.
Community leader Rudy Corpuz Jr., with United Playaz, said San Francisco took a big step toward being less violent.
"We got a bazooka off the streets. We got a cannon ball off the streets. We got assault rifles. We got everything that you can name that could destroy a whole universe and we get rid of them within hours," he told ABC7 News.
Buyback organizers added that the event succeeded because of its "no questions asked" policy for people who surrender guns.