Noel Ralston taught and conducted research at the University of Missouri (1937-1939), Cornell University (1939-1943), and the University of California at Davis (1942-1949) before becoming Associate Professor in Michigan State University's Dairy Department in 1949. He was appointed head of the Department in 1955 and Director of the University Cooperative Extension Service and Assistant Dean of the College of Agriculture in 1959. He was appointed Deputy Administrator of Federal Extension in 1966 to work with all Land Grant University State Cooperative Extension Services. He was then appointed Deputy Director (1968) and Associate Director (1969) of Science and Education in the Secretary's office of the U.S. Department of Agriculture during three presidential terms. As such, he served as Vice Chairman of the 1970 Working Conference of Representatives of Higher Education in Agriculture in Paris, was chief of the delegation to Copenhagen for the World Conference on Agricultural Education and Training, and was Vice Chairman of the delegation to Tokyo for UNESCO's Third International Conference on Adult Education.
In 1957, he was named a Fellow of the American Association for the Advancement of Science and has been listed in Who's Who in America.