George W. Arrowsmith (18 April 1839-1 July 1863) was a Union Army lieutenant-colonel who served in the American Civil War. Born in Middletown Township, New Jersey, he joined the 26th New York Infantry Regiment in May 1861 and served as Assistant Adjutant General from August to November 1862, after which he became lieutenant-colonel of the 157th New York Infantry Regiment. He opted to stay with his men at the Battle of Gettysburg despite falling ill, and he was shot in the forehead while defending the XI Corps line north of the town.