The president pro tempore of the California State Senate (President Pro Tem) is the chief executive and highest-ranking member the California State Senate and serves as chair of the Senate Rules Committee.

The Pro Tem is chosen at the beginning of each two-year session, via election by all the other senators-elect.

[1] The current President pro tempore is Mike McGuire, a Democratic member from the 2nd district, who was sworn in on February 5, 2024.

[3] If the President Pro Tempore is absent, another Senator appointed by the President pro tempore can act as chair.

[4] The President pro tempore has a responsibility to "secure the prompt and businesslike disposition of bills and other business before the Senate.