Harry Theophilus Toulmin (March 4, 1838 – November 12, 1916) was a United States district judge of the United States District Court for the Southern District of Alabama.

Born in Mobile County, Alabama, Toulmin read law to enter the bar in 1860. He was in private practice in Mobile, Alabama in 1860. He was a Confederate States Army Colonel from 1861 to 1865, then resumed private practice in Mobile. He was a member of the Alabama House of Representatives from 1870 to 1872. He was a Judge of the 6th Judicial Circuit of Alabama from 1874 to 1880, then a Judge of the 1st Judicial Circuit of Alabama from 1880 to 1882, the change due to realignment of the circuits.^[1]

Toulmin was nominated by President Grover Cleveland on December 13, 1886, to the United States District Court for the Southern District of Alabama, to a new seat authorized by 24 Stat. 213. He was confirmed by the United States Senate on January 13, 1887, and received his commission the same day. His service terminated on November 12, 1916, due to his death in Toulminville, Alabama.^[1]