Grand-Gosier is a commune in Haiti, located in the Belle-Anse Arrondissement within the Sud-Est department. The Sud-Est department occupies the southeastern part of the country, and the Belle-Anse Arrondissement is one of its administrative divisions.
The commune has a population of 17,059 inhabitants. As a commune, Grand-Gosier serves as a local administrative unit within Haiti's system of territorial organization.