The village of Gassin was mentioned in the cartularies of the abbey of Verne in Collobrières in 1190 and the Saint-Victor abbey of Marseille in 1234. It then appeared under the name Garcin, which it kept until the mid-18th century. This denomination of Indo-European origin would have been formed, according to the toponymist Charles Rostaing, from the roots kar (perched stone) and sen (hill, built on a rock), an etymology shared with the municipalities of La Crau and Cassis.