Echinococcosis is a multisystem disease and has propensity to involve any organ, an unusual anatomical site, and can mimic any disease process. The hydatid cyst of the mesenteries known to occur secondary to hepatic involvement but occasional cases of his primitive form has also been reported. We report here one such case of primitive mesenteric hydatid cyst herniated through inguinal canal in a 5-yr-old boy, admitted to our Pediatric Surgery Department of Children's Hospital in Tunis, Tunisia in 2015.