Elias Warner Leavenworth (December 20, 1803 – November 25, 1887) was an American lawyer and politician.

He was born in Canaan, New York, and lived there before moving to Great Barrington, Massachusetts, in 1806.

[1] His principal home, a mansion at 607 James Street in Syracuse, was a significant Greek Revival style structure where he received visitors of national and international stature.

In 1839, he was named supervisor of the old town of Salina, the first election at which the Democrats had been beaten for 15 years.

[1] In 1861 President Abraham Lincoln appointed Leavenworth the United States' commissioner for the convention with Granadine Confederation in 1861 and 1862.