Trophime-Gérard, marquis de Lally-Tollendal (5 March 1751 – 11 March 1830) was a French politician.
Born in Paris into an old aristocratic family, he was the legitimized son of Thomas Arthur de Lally, who served as viceroy in India under King Louis XIV, and only discovered the secret of his birth on the day of his father's execution (May 9, 1766), when he devoted himself to clearing his father's memory. He was supported by Voltaire, and in 1778 succeeded in persuading King Louis XVI to annul the decree which had sentenced the Comte de Lally, but the parlement of Rouen, to which the case was referred back, in 1784 again decided in favour of Lally's guilt. The case was retried by other courts, and Lally's innocence was never fully admitted by the French judges.
In 1779 Lally-Tollendal bought the honorary title of Grand bailli of Étampes, and in 1789 was a deputy to the Estates-General for the noblesse of Paris. He played some part in the early stages of the French Revolution, but, as a conservative, quickly rejected more profound changes.
He joined the opposition to the strict regime of the Marquis de Mirabeau, and condemned the decisive rejection of the Ancien Régime by the National Constituent Assembly, begun by the Tennis Court Oath and confirmed by the abolition of feudalism on 4 August 1789. Later in the year he emigrated to Great Britain.