Marie-Charles-César de Faÿ, comte de la Tour-Maubourg (born 11 February 1757 at Motte-Galaure, Drôme - died 28 April 1831 in Paris) was a French soldier and politician during the French Revolution and the First French Empire. His father was Claude Florimond de Faÿ (1712–1790); his mother was Vacheron Bermont Marie Françoise (b. 1712).
de Faÿ was colonel of the Regiment of Soissons in 1789.
He was appointed to the nobility of Puy-en-Velay in the Estates General. He was a friend of Gilbert du Motier, marquis de Lafayette. De Faÿ was one of the first nobles to join the Third Estate. He was representative to Nord and Pas de Calais.
De Faÿ was charged, with Antoine Barnave and Jerome Pétion, to return the royal family to Paris following its flight to Varennes (June 1791). His devotion on this occasion was misunderstood by Marie-Antoinette. However, in her memoirs, Madame Tourzel, witness of the facts, paid tribute to his dedication to the royal family.
De Faÿ was Colonel of the 3ème régiment de chasseurs à cheval from 1791 to February 1792. With the separation of the National Constituent Assembly, he accompanied the marquis de Fayette with the Army of the Center in 1792 and emigrated with him after the dismissal by Louis XVI on 10 August 1792. Captured at Rochefort, Belgium, with Lafayette, and imprisoned by Austria, he was released after the treaty of Campo-Formio (18 October 1797) and lived in exile in Hamburg.