Hayden G. Melvin, 72, a retired Prince George's County car dealer who was active in Democratic politics, died of cardiac arrest Wednesday in a hospital in Baltimore.

Mr. Melvin came to this area in 1946 and founded Melvin Motors, a used car dealership in Bowie, later that year. He also operated Melvin Nash, a new car dealership, and was active in real estate in Prince George's County for several years. He retired as president of Melvin Motors in 1972.

He was president of the 14th District Democratic Club in Bowie for three terms during the 1960s. He also had served on the Prince George's County Library Board.

He was a charter member of the Collington Masonic Lodge in Bowie and member of the Bowie Kiwanis Club.

Mr. Melvin was a native of Ingold, N.C., and attended Lenior Rhyne College in Hickory, N.C. He lived in New Jersey and Pennsylvania before moving to Bowie in 1946. He had lived in Catonsville since 1948.

His first wife, Mary Helene, died in 1972.

Mr. Melvin's survivors include his wife, Dorothy, of Catonsville; a son, Daniel H., and a daughter, Martha E. Mellin, both of Bowie; a sister, Alma Horne of Kinston, N.C., and four grandchildren.