The 2004 California State Assembly elections were held on November 2, 2004. California's State Assembly in its entirety comes up for election in even numbered years. Each seat has a two-year term and members are limited to three 2-year terms. All 80 biennially elected seats in the Assembly were up for election this year. It was expected that the Democrats would retain control of the Assembly, which they did. While some seats were close races, no opposing party challenges to incumbents were successful on either side and thus, there were no changes to the party balance.

The 2002 California State Assembly elections were held on November 5, 2002. California's State Assembly in its entirety comes up for election in even numbered years. Each seat has a two-year term and members are limited to three 2-year terms. All 80 biennially elected seats in the Assembly were up for election this year. Democrats retained control of the Assembly, though they lost two seats.