The Battle of Sluys (; ), also called the Battle of l'Écluse, was a naval battle fought on 24 June 1340 between England and France. It took place in the roadstead of the port of Sluys (French "Écluse"), on a since silted-up inlet between Zeeland and West Flanders. The English fleet of 120–150 ships was led by Edward III of England and the 230-strong French fleet by the Breton knight Hugues Quiéret, Admiral of France, and Nicolas Béhuchet, Constable of France. The battle was one of the opening engagements of the Hundred Years' War.