Martin "Marty" Maher, Jr. (June 25, 1876 – January 17, 1961) was an Irish immigrant from Ballycrine near Roscrea, County Tipperary, Ireland, who joined the United States Army in 1898 and rose to the rank of master sergeant.

He served as a swimming instructor at the United States Military Academy, West Point, New York, from 1899 to 1928.

Maher retired from the army in 1928 and stayed at West Point as a civilian employee in the athletic department.

His autobiography Bringing Up the Brass: My 55 Years at West Point, co-written by Colonel Russell Reeder and Nardi Reeder Campion, and with a foreword by Dwight D. Eisenhower, was published in 1951 by David McKay Company Inc. Maher died on January 17, 1961, at the age of 84 and is interred in the West Point Cemetery.

Maher was the subject of the 1955 film The Long Gray Line, starring Tyrone Power and Maureen O'Hara.