John Watson Erwin (April 5, 1894–March 3, 1972) was an American college basketball coach.

Born in Spartanburg, South Carolina, in 1894, he attended Clemson College from 1911 to 1914, where he excelled in both tennis and basketball.

Alongside his brother James, he won the Southern Intercollegiate Athletic Association doubles championship in 1913.

[1] Erwin played on Clemson's first basketball team in 1912, and was captain and player-coach in the 1914 season.

This biographical article relating to a United States basketball figure is a stub.