Gérard Diffloth (born Châteauroux, 1939) is a retired linguistics professor, formerly of the University of Chicago, Chicago, Illinois, and Cornell University, Ithaca, New York. He received his Ph.D. from UCLA, after a dissertation on the Irula language. Diffloth is a leading specialist in the Austroasiatic languages.
Diffloth is known for his widely cited 1974 and 2005 classification of the Austroasiatic languages.
- Diffloth, Gérard, and Dennis, John Value. Socio-Cultural Matters in the Upland Watersheds of Southern Laos: A Personal Report. 1999.
- Diffloth, Gérard. The Ethnic Situation in the Central Highlands. 1998.
- Diffloth, Gérard. Report to Halcrow. 1995.
- Diffloth, Gérard. A History of the Khmer Language. [199-].
- Diffloth, Gérard. The Dvaravati Old Mon Language and Nyah Kur. Monic language studies, vol. 1. Bangkok, Thailand: Chulalongkorn University Print. House, 1984. ISBN 974-563-783-1
- Diffloth, Gérard. The Wa languages. Berkeley : Dept. of Linguistics, University of California, 1980.
- Diffloth, Gérard. An Appraisal of Benedict's Views on Austroasiatic and Austro-Thai Relations. Kyoto: Center for Southeast Asian Studies, Kyoto University, 1976.
- Diffloth, Gérard, and Zide, Norman H. Austroasiatic Number Systems. 1976.
- Diffloth, Gérard. Proto-Mon–Khmer Final Spirants. Kyoto: Center for Southeast Asian Studies, Kyoto University, 1976.
- Diffloth, Gérard. The Irula Language, a Close Relative of Tamil. Thesis—University of California, Los Angeles, 1968.