Thomas Amos Rogers Nelson (March 19, 1812 – August 24, 1873) was an American attorney, politician, and judge, active primarily in East Tennessee during the mid-19th century. He represented Tennessee's 1st Congressional District in the 36th U.S. Congress (1859–1861), where he gained a reputation as a staunch pro-Union southerner. He was elected to a second term in 1861 on the eve of the Civil War, but was arrested by Confederate authorities before he could take his seat.