John George Chalmers (August 17, 1874 – June 8, 1962) was an American football, basketball, and baseball coach. He served as the head football coach at Franklin & Marshall College (1902), the University of Iowa (1903–1905), Columbia College in Dubuque, Iowa, now known as Loras College, (1907–1914), and the University of Dubuque (1914–1924), compiling a career college football record of 100–47–8. Chalmers was also the head men's basketball coach at Iowa for one season (1904–1905), tallying a mark of 6–8, and the baseball coach at Iowa for two seasons (1904–1905) and at Columbia College from 1915 to 1921.