Following his playing career, Shannon became head coach at Topeka High School in Kansas, where he coached from 1950 to 1954 before becoming an assistant to Tex Winter at Kansas State. In 1964, Shannon was named head coach of Virginia Tech. Shannon coached the Hokies to a 104-67 record and its best NCAA Tournament finish in 1967, reaching the Mideast Regional final before falling to Dayton. In 1971, Shannon resigned to join Virginia Tech's physical education faculty full-time. Shannon was also coach of the 1960 Puerto Rican basketball team in the 1960 Olympics.