The 7th Maine Infantry Regiment was a regiment of the Union Army from Maine which was active from 21 August 1861 to 21 August 1864 during the American Civil War. Organized at Augusta, the regiment was attached to the Army of the Potomac from the Peninsula Campaign to the Battle of Fort Stevens, after which it took part in the Valley Campaigns of 1864. The regiment was mustered out at Charlestown, West Virginia in 1864.