Hydatidosis is endemic in Morocco, its pelvic location is rare and misleading. We report the observation of a 34-year-old 2th G 2th P patient admitted for a pelvic mass associated with gravity signs without other accompanying signs. Ultrasound and CT scans located a right anterior lateral septum anechoic mass. The diagnosis of pelvic hydatid cyst is made intraoperatively. The treatment consisted of a resection of the protruding dome. The evolution was favorable.