Naval Weapons Station Seal Beach was commissioned in 1944 at the height of World War II as a Naval Ammunition and Net Depot. It served two primary purposes at that time: housing and loading ammunition on the Fleet ships preparing to depart for war, and servicing the anti-submarine nets used to protect fleet bases all around the world.

Since World War II, Seal Beach has become the Navy's major ordnance storage facility on the West coast. The Navy's Munitions Command is Seal Beach's major tenant command and provides the loading of missiles, torpedoes, countermeasure devices and conventional ammunition onto cruisers, destroyers, frigates and amphibious assault vehicles. It is has convenient access to the fleet at Long Beach and San Diego and Long Beach Harbor provides an extra port for larger ships.

The World War II National Submarine Memorial- West is located here right outside the station's entrance so it is available to the public. It honors the 52 submarines and 3,000 lives that were lost during the war.