William Taylor Thornton (February 9, 1843 – March 16, 1916) was an American politician who served as the 15th Governor of New Mexico Territory from 1893 to 1897.

He joined the Confederate States Army during the American Civil War, and served in the personal guard of General Sterling Price, and later in a company commanded by his brother Paul.

After the war Thornton passed the bar and began to practice law in Clinton, Missouri, and served two terms on the town council.

He began to practice law in Santa Fe, New Mexico, and eventually formed a partnership with Thomas B. Catron.

Thornton was also involved in several businesses, including mining, cattle ranching, real estate development, and land speculation.