Thériault is a surname. Notable people with the surname include:
Bernard Thériault (born 1955), Canadian politician
Bruno Thériault (1917–2005), blind piano tuner, regional administrator for the Canadian National Institute for the Blind
Camille Thériault (born 1955), Canadian politician, former premier of New Brunswick
Charles Theriault, Maine politician
Denis Thériault (born 1959), Canadian writer
Edward Joseph Thériault (1901–1968), Liberal party member of the Senate of Canada
Élisée Thériault (1884–1958), lawyer and political figure in Quebec
Éric Thériault (born 1967), Canadian cartoonist
Gérard Charles Édouard Thériault (1932–1998), former Canadian Chief of Defense Staff
Harold Theriault, Canadian politician
Janine Theriault (born 1975), Canadian actress
Jean-Yves Thériault, bassist from Canadian metal group Voivod
Jean-Yves Thériault (kickboxer) (born 1955), Canadian kickboxer
Lévite Thériault (1837–1896), land owner and political figure in New Brunswick
Lise Thériault (born 1966), Quebec politician
Lyn Thériault, formerly known as Lyn Faust, politician in Montreal, Quebec, Canada
Mathieu Corbeil-Thériault (born 1991), Canadian ice hockey goaltender
Milaine Thériault (born 1973), Canadian skier
Nicole Theriault, known as Nikki, Thai singer
Norbert Thériault (born 1921), Canadian politician
Paul Thériault, Canadian politician, former leader of the Yukon Liberal Party
Roch Thériault (1947–2011), religious leader
Sean Theriault, American professor
Serge Thériault (born 1948), Quebec comedian and actor
Yves Thériault (1915–1983), Canadian author