Bainbridge Wadleigh (January 4, 1831 - January 24, 1891) was a United States Senator from New Hampshire. Born in Bradford, he attended the common schools and Kimball Union Academy (Plainfield, New Hampshire). He studied law, was admitted to the bar in 1850 and commenced practice in Milford. He served six terms as town moderator and was a member of the New Hampshire House of Representatives in 1855-1856, 1859-1860, and from 1869 to 1872.
Wadleigh was elected as a Republican to the U.S. Senate and served from March 4, 1873, to March 3, 1879; he was an unsuccessful candidate for reelection in 1878. While in the Senate he was chairman of the Committee on Patents (Forty-fourth and Forty-fifth Congresses) and a member of the Committee on Privileges and Elections (Forty-fifth Congress).
He resumed the practice of law in Boston, where he died in 1891; interment was in West Street Cemetery, Milford.