Lombard Street is an east–west street in San Francisco, California, that is famous for a steep, one-block section with eight hairpin turns. The street stretches from The Presidio east to The Embarcadero (with a gap on Telegraph Hill). Most of Lombard Street's western segment is a major thoroughfare designated as part of U.S. Route 101. The famous one-block section, claimed to be "the crookedest street in the world", is located along the eastern segment in the Russian Hill neighborhood. It is a major tourist attraction, receiving around two million visitors per year and up to 17,000 per day on busy summer weekends, as of 2015.

San Francisco surveyor Jasper O'Farrell named the road after Lombard Street in Philadelphia.