Chylolymphatic mesenteric cysts are extremely rare among children. Herein we report a case of a 3-month old infant that was admitted to the Emergency Department due to repeated vomiting. Preoperative ultrasonography demonstrated the presence of a thin-walled multiloculated cystic lesion in the right abdomen. Patient underwent then elective surgical excision. Histopathological examination documented the diagnosis of cystic lymphangioma type III, according to Lozanoff classification.