William Wilson Elwang (November 16, 1865 - November 28, 1938) was a Presbyterian minister, teacher, and author. He served as historian of the Sigma Alpha Epsilon fraternity from 1887.
His thesis studying the "Negroes" of Columbia, Missouri and the "race problem" was conducted via canvassing black households. Elwang depicted the African American community in Columbia as "shiftless" and recommended manual labor colleges. Elwang's conclusions included a declining African American population in Columbia due to birth and death rates and a disappearance of "Negroes" due to interbreeding with whites. Raymond Weeks criticized the book and stated it included false accusations of thieving in a letter to W. E. B. Du Bois. He married twice and had a daughter. He died in Columbia and is buried in the Columbia Cemetery in Columbia, Missouri. The State Historical Society of Missouri has a collection of his papers.