Jeannot Castonguay (born 1 September 1944 in Saint-Quentin, New Brunswick) was a Liberal member of the Canadian House of Commons from 2000 to 2004. He won the Madawaska—Restigouche electoral district in New Brunswick to become a member of the 37th Canadian Parliament. He is a career physician.
Castonguay left political life in 2004 as he did not seek re-election. Jean-Claude D'Amours won the Madawaska-Restigouche riding for the Liberal party that year.