San Francisco and San Mateo county officials have been fighting for years to stop gun shows at the Cow Palace, which is located partly in both San Francisco and Daly City in an area that struggles with violence and gang activity.
Other counties have successfully blocked gun shows on county fairgrounds and similar facilities by passing ordinances.
But because the Cow Palace is owned and operated by the state, the shows have continued there despite local opposition.
Senate Bill 475 would require both the San Mateo and San Francisco board of supervisors to pass resolutions approving a gun show at the Cow Palace before such an event could be held.
"For years, residents, community organizations and elected leaders from the neighborhoods surrounding the Cow Palace have asked to have a voice in the decision to hold gun shows in their backyards, but they have been ignored," Leno said.
Leno authored two previous bills that would have banned gun shows at the Cow Palace. The most recent, SB 585, was vetoed by Gov. Arnold Schwarzenegger.
Brown has until Oct. 13 to act on the bill.