Robert Orr Harris (November 8, 1854 – June 13, 1926) was a U.S. Representative from Massachusetts, son of Benjamin Winslow Harris. Born in Boston, Massachusetts, Harris attended the common schools and Phillips Exeter Academy, Exeter, New Hampshire.He graduated from Harvard in 1877.He studied law.He was admitted to the bar in 1879 and practiced in Boston and Brockton, Massachusetts from 1879 to 1902.He served as member of the State house of representatives in 1889.He served as district attorney for the southeastern district of Massachusetts 1891-1901.He served as associate judge of the superior court of Massachusetts from June 4, 1902, to March 1, 1911.