The California Highway Patrol (CHP) is the principal state police agency for the U.S. state of California. The CHP has primary patrol jurisdiction over all California highways and roads and streets outside city limits, and can exercise law enforcement powers anywhere within the state. The California Highway Patrol can assist local and county agencies and can patrol major city streets along with local and county law enforcement, state and interstate highways, and is the primary law enforcement agency in rural parts of the state.

State police, provincial police or regional police are a type of sub-national territorial police force found in nations organized as federations, typically in North America, South Asia, and Oceania. These forces typically have jurisdiction over the relevant sub-national jurisdiction, and may cooperate in law enforcement activities with municipal or national police where either exist.