Robert Cook Folwell Jr. (February 17, 1885 – January 8, 1928) was an American football player and coach. He served as the head coach at Lafayette College (1909–1911), Washington & Jefferson College (1912–1915), the University of Pennsylvania (1916–1919), and the United States Naval Academy (1920–1924), compiling a career college football record of 106–29–9. Folwell then moved to the professional ranks, coaching the New York Giants of the National Football League (NFL) in 1925, the Philadelphia Quakers of the American Football League in 1926, and the Atlantic City Roses of the Eastern League of Professional Football in 1927.