USS Colorado (BB-45) was a battleship of the United States Navy that was in service from 1923 to 1947. She was the lead ship of the Colorado class of battleships. Her keel was laid down on 29 May 1919, by the New York Shipbuilding Corporation. She was launched on 22 March 1921, and commissioned on 30 August 1923. She was armed with eight 16-inch (406 mm) guns and fourteen 5-inch (127 mm) deck guns; two 5-inch guns were removed in an overhaul.

She was the third US navy ship named Colorado, but only the second named for the 38th state, the first Colorado was named for the Colorado River.

Colorado and sailed through the Pacific during the interwar years. She also underwent a further refit, during which her four 3-inch (76 mm) anti-aircraft guns were replaced with an equal number of took her maiden voyage in 1923, to Europe. She later operated with the Battle Fleet5 in (127 mm)/25 cal guns.

During the early part of World War II, Colorado undertook a defensive patrol near the Golden Gate Bridge in May 1942, to stop a possible Japanese invasion. She then sailed to Fiji, to stop any further Japanese advance into the Pacific. Next, she supported the landings on Tarawa, the Marshall Islands, Saipan, Guam, and Tinian. On 24 July 1944, during the shelling of Tinian, Colorado received 22 shell hits from shore batteries, but continued to support the invading troops until 3 August. She later arrived in Leyte Gulf on 20 November 1944, to support American troops fighting ashore. On 27 November, she was hit by two kamikazes which caused moderate damage.

After that, Colorado sailed to Luzon on 1 January 1945, where she participated in the preinvasion bombardments in Lingayen Gulf. She returned to Okinawa on 6 August and sailed from there to Japan for the occupation of the country, arriving in Tokyo on 27 August. Departing Tokyo Bay on 20 September, she arrived at San Francisco on 15 October. She was placed out of commission in reserve in Pearl Harbor on 7 January 1947, and sold for scrapping on 23 July 1959. She won seven battle stars during her service. Many of Colorado's anti-aircraft guns are in museums across the state of Colorado (her bell and teak decking are also in museums and the USO in the Seattle-Tacoma airport) or mounted on themuseum ship Olympia.