The Mayor of San Francisco is the head of the government of San Francisco, California. The mayor serves a four-year term and is limited to two terms. Because San Francisco is a consolidated city-county, the mayor is the head of government both of the county and city; however, both entities are governed by a combined set of governing bodies.

Gavin Newsom is the 42nd mayor of San Francisco. He was re-elected to a second term in 2007.