California State Military Museum, Military history museum in Sacramento, US

The California State Military Museum occupied a building at 1119 Second Street in Old Sacramento State Historic Park. Its entrance held the Global War on Terrorism Wall of Honor, a black granite memorial listing service members who died at the Pentagon on September 11, 2001, and in the Afghanistan and Iraq campaigns, with rank, branch and age. Inside, the Major General Walter P. Story Memorial Library held over 10,000 volumes, including original rosters of early California Militia units.

The museum began in 1991 under Governor Pete Wilson. Eleven years later Governor Gray Davis made it permanent under the California State Military Department with permanent funding, and on 13 July 2004 Governor Arnold Schwarzenegger designated it the State's official Military Museum. It closed indefinitely in March 2014 amid a dispute between its operating foundation and the California Military Department, plus state budget constraints; a new site is under development.

The museum's name and role come from its status as the state's official military museum, declared by Governor Arnold Schwarzenegger on 13 July 2004. Its five satellite sites are at Camp Roberts in southern Monterey County, Camp San Luis Obispo, Fresno Air National Guard Base, the Los Alamitos Joint Forces Training Base in Orange County and the National Guard Armory in San Diego.

The museum sits in Sacramento with its main collection available to visitors in person. For deeper research needs, people can also access additional materials through several branch locations across the state.

The museum displays personal items and diaries from soldiers across different conflicts, ranging from the Mexican-American War to recent military operations. These individual objects give visitors direct insight into the lived experiences of people who served in combat.