The California State Capitol is the seat of the California state government, located in Sacramento, the state capital of California. The building houses the chambers of the California State Legislature, made up of the Assembly and the Senate, along with the office of the governor of California. The Neoclassical structure, designed by Reuben S. Clark, was completed between 1861 and 1874. Located at the west end of Capitol Park and the east end of the Capitol Mall, the building was added to the National Register of Historic Places in 1973. The California State Capitol Museum is housed on the grounds of the capitol.

The government of California is the governmental structure of the U.S. state of California as established by the California Constitution. California uses the separation of powers system to structure its government. It is composed of three branches: the executive, consisting of the governor of California and the other constitutionally elected and appointed officers and offices; the legislative, consisting of the California State Legislature, which includes the Assembly and the Senate; and the judicial, consisting of the Supreme Court of California and lower courts. There is also local government, consisting of counties, cities, special districts, and school districts, as well as government entities and offices that operate independently on a constitutional, statutory, or common law basis. The state also allows direct participation of the electorate by initiative, referendum, recall and ratification.