William Parker Shadoan (December 8, 1894 – June 20, 1974) was an American football, basketball, and baseball coach and military officer.

He served as head football, basketball, and baseball coach at Valparaiso University during the 1923–24 and 1924–25 academic years.

He served in the United States Army during the Pancho Villa Expedition and with the American Expeditionary Forces in France during World War I.

He reached the rank of colonel and later served as the superintendent of a number of military schools.

This biographical article relating to a college football coach first appointed in the 1920s is a stub.