Battery M, 1st Missouri Light Artillery Regiment was an artillery battery unit from Missouri that served in the Union Army during the American Civil War. The 1st Missouri Light Artillery Regiment was formed 1 September 1861. Battery M fought at Island Number Ten, 1st Corinth, Iuka, and 2nd Corinth in 1862. The unit participated in several battles during the Vicksburg campaign in 1863. Battery M fought at Meridian, Fort De Russy, Pleasant Hill, Yellow Bayou, and Tupelo in 1864. After serving on garrison duty in west Tennessee, the battery mustered out on 25 July 1865.