Eli H. Janney (November 12, 1831 – June 16, 1912), aka Eli Hamilton Janey or simply Eli Janney, was the inventor of the modern knuckle coupler that replaced link and pin couplers on North American railroads.

Janney's coupler and the Westinghouse air brake are generally regarded as being the two most significant safety inventions in U.S. railroads between the end of the Civil War and 1900.