Louis de Rouvroy, duc de Saint-Simon, French soldier and diplomat (d. 1755)

Louis de Rouvroy, duc de Saint-Simon, GE (16 January 1675 – 2 March 1755), was a French soldier, diplomat, and memoirist. He was born in Paris at the Hôtel Selvois, 6 rue Taranne (demolished in 1876 to make way for the Boulevard Saint-Germain). The family's ducal peerage (duché-pairie), granted in 1635 to his father Claude de Rouvroy (1608–1693), served as both perspective and theme in Saint-Simon's life and writings. He was the second and last Duke of Saint-Simon.

His enormous memoirs are a classic of French literature, giving the fullest and most lively account of the court at Versailles of Louis XIV and the Régence at the start of Louis XV's reign.