Louis François, duc de Boufflers, comte de Cagny (January 10, 1644 - August 22, 1711) was a Marshal of France.

He entered the army and saw service in 1663 at the siege of Marsal , becoming in 1669 colonel of dragoons. In the conquest of Lorraine (1670) he served under Marshal de Créqui . In Holland he served under Turenne, frequently distinguishing himself by his skill and bravery; and when Turenne was killed by a cannon-shot in 1675 he commanded the rear-guard during the retreat of the French army. He was already a brigadier, and in 1677 he became maréchal de camp .

He served throughout the campaigns of the time with increasing distinction, and in 1681 became lieutenant-general. He commanded the French army on the Moselle, which opened the War of the League of Augsburg with a series of victories; then he led a corps to the Sambre, and reinforced Luxembourg on the eve of the battle of Fleurus (1690).

In 1691 he acted as lieutenant-general under the king in person; and during the investment of Mons he was wounded in an attack on the town. He was present with the king at the siege of Namur in 1692, and took part in the victory of Steinkirk. For his services he was raised in 1692 to the rank of Marshal of France, and in 1694 was made a duke.

In 1694 he was appointed governor of French Flanders and of the town of Lille. By a skilful manoeuvre he threw himself into Namur in 1695, and only surrendered to his besiegers after he had lost 8,000 of his 13,000 men. In the conferences which terminated in the peace of Ryswick he had a principal share. During the following war, when Lille was threatened with a siege by Marlborough and Eugène, Boufflers was appointed to the command, and made a most gallant resistance of three months.

He was rewarded and honoured by the king for his defence of Lille, as if he had been victorious. It was indeed a species of triumph; his enemy, appreciating his merits, allowed him to dictate his own terms of capitulation. In 1708 he was made a peer of France. In 1709, when the affairs of France were threatened with the most urgent danger, Boufflers offered to serve under his junior, Villars, and was with him at the battle of Malplaquet. Here he displayed the highest skill, and after Villars was wounded he conducted the retreat of the French army without losing either cannon or prisoners. He died at Fontainebleau on August 22, 1711.