Thomas Louis Glenn (February 2, 1847 – November 18, 1918) was an attorney and politician from Idaho.

Glenn served a single term as a Populist in Congress from 1901 to 1903, representing the state at-large.

During the American Civil War served in the Confederate States Army as a member of Company F, Second Kentucky Cavalry Regiment.

He was subsequently captured, and imprisoned at Transylvania University until he was paroled in September.

Glenn studied law, was admitted to the bar in 1890, and began a practice in Montpelier, Idaho.