Guillaume de Villaret (Occitan: Guilhem del Vilaret) (d. 1305), a native of Languedoc-Roussillon was the 24th Grand Master of the Knights Hospitallers,[1] a position he held from 1296 to his death. He was succeeded by his nephew, Foulques de Villaret, whose career he had done much to advance.

In 1300, in response to the urgent remonstrances of the knights, he appeared in Cyprus. His Order participated in an ill-fated expedition with other Cypriots, meaning the Knights Templar, the Teutonic Knights, and the Kingdom of Jerusalem, to launch coastal raids along the Egyptian, Palestine and Syrian coasts in 1300. The Cypriots, under King Henry II, then sent a land-based source to the island of Arwad, in an attempt to retake the coastal city of Tortosa. There had been some attempt to do this in concert with forces from the Mongol Ilkhanate; however the promised Mongol troops did not arrive, the Cypriots eventually had to retreat from Ruad, and the island was re-taken by the Egyptian Mamluks a year later.