Harry Nathan Tuthill (July 30, 1870 – January 31, 1935) was an American athletic trainer.

He served two year in the United States Navy before returning to Saginaw where he worked in a boiler factory and later as a bellhop.

[2] While living in New York and after working as an entertainer, Tuthill began training footracers and then boxers.

He was a trainer in Major League Baseball for the New York Giants (1904-1907) and Detroit Tigers (1907-1921) and in college football for the Army Cadets (1911-1915) and Michigan Wolverines (1916-1917).

He was also the trainer or cornerman for many boxers, including world champions Terry McGovern, Young Corbett II, Young Griffo, Kid McCoy, Stanley Ketchell, and Honey Mellody, as well as Mysterious Billy Smith and George "Elbows" McFadden.