Willard Russell Letlow (October 5, 1913 – October 12, 1987) was an American football guard and tackle who played professionally for the Green Bay Packers of the National Football League (NFL).

Letlow played his college career at the University of San Francisco.

Prior to the 1936 NFL draft, college players were free agents that could sign with an NFL team; Letlow had signed with the Chicago Cardinals prior to the draft.

He was named to the All-Star game, the predecessor to the Pro Bowl in 1938 and 1939.

Letlow was inducted into the Green Bay Packers Hall of Fame in 1972.