Westel Willoughby, Jr. (November 20, 1769 - October 3, 1844) was a U.S. Representative from New York.
Born in Goshen, Connecticut, Willoughby moved to Newport, New York. He studied medicine and engaged in practice. He was appointed judge of the court of common pleas of Herkimer County in 1805 and served until 1821. He served as president of the Herkimer County Medical Society 1806-1816 and 1818-1836. He served in the State assembly in 1808 and 1809.
He served as president of the College of Physicians and Surgeons for the Western District of New York 1812-1844.
He served as member of the medical staff of the militia and served in the War of 1812. He successfully contested as a Democratic-Republican the election of William S. Smith to the Fourteenth Congress and served from December 13, 1815, to March 3, 1817. Founded the town of Willoughby, Ohio, and also Willoughby College (now a part of Syracuse University). He died in Newport, New York, October 3, 1844. He was interred in the First Baptist Church Cemetery.