California's 20th senatorial district is one of 40 California State Senate districts. It is currently represented by of .
The district encompasses most of the San Fernando Valley section of northern Los Angeles, including Burbank, Van Nuys, Reseda, Canoga Park, Tujunga, Sun Valley, Shadow Hills, Lake View Terrace, Arleta, Panorama City, Pacoima, Mission Hills, San Fernando, and Sylmar.
Due to redistricting, the 20th district has been moved around different parts of the state. The current iteration resulted from the 2021 redistricting by the California Citizens Redistricting Commission.