Louis Charles Marie de La Trémoille (28 March 1863–17 June 1921), 10th duc de Thouars, was a French nobleman and the son of Louis Charles de La Trémoille and his wife, Marguerite-Jeanne Tanneguy-Duchâtel.
La Trémoille was a deputy for Gironde from 1906 to 1919, and mayor of Margaux from 1904 to 1919. He was a member of the democratic left.
On 1 February 1892, he married Hélène Marie Léonie Pillet-Will (27 January 1875–24 March 1964), the daughter of count Frédéric Pillet-Will, and his wife, Jeanne Marie Clotilde Briatte. They had five children:
Charlotte (1892–1971); who married Henri Florent Lamoral, prince de Ligne (1881–1967), grandson of prince Eugène de Ligne d'Amblise et d'Epinoy.
Marguerite (1894–1939); who married the duc de Blacas, Stanislas de Blacas d'Aulps (1885–1941).
Hélène (1899–1972); who married the duc de La Roche-Guyon, Gilbert de La Rochefoucauld (1889–1964).
Antoinette (1904–1996); who married Henri duc d'Ursel, and later married the marquis de Bonneval, Guy Bernard du Val (1898–1987).
Louis Jean Marie (1910–1933) his successor.