Fussell was born in Pasadena, CA and grew up there . His father, Paul Longstreth Fussell (15 January 1895-16 July 1973), was a corporate lawyer in Los Angeles with the firm of O’Melveny & Myers. His mother was born Wilhma Wilson Sill in Illinois 21 August 1893 and died 23 March 1971. In 1943 Fussell earned a B.A. degree from Pomona College. Thereafter he joined the U.S. Navy, serving aboard a destroyer in the Pacific Theater of Operations during World War II. He received a Ph.D. from Harvard University in 1949.

Fussell first taught at the University of California at Berkeley. He refused to sign a loyalty oath during the era of Sen. Joseph McCarthy's "communist-hunting" in the early 1950s, losing his professorship as a result. Fussell then went to Pomona College, his alma mater, where he taught American Literature. After teaching at the Claremont Graduate School, Fussell joined the faculty of UC-San Diego. He retired in 1991 .

During his retirement, Fussell lived in Paris and Rome. He still wrote, especially about Henry James, Chateaubriand, and Balzac . Fussell died in August 2002 in La Jolla, CA .