Hydatid disease is a parasitic disease, which is caused by echinococcus and often located in the liver and lung but occasionally found in other organs. Only one previous study reported localization in the mesorectum. In this case report, we present a 27-year-old male, as a second case in the literature, with a hydatid cyst located in the mesorectum. Abdominopelvic computed tomography revealed cystic masses localized in the mesorectum with no pulmonary or hepatic involvement. Preoperative cyst hydatid IgG (1/1000) was positive, and the preliminary diagnosis was hydatid disease. The patient underwent partial cystectomy. Macroscopic and microscopic examination of the specimens confirmed the hydatid cyst. This case report demonstrates that hydatid disease should be taken into consideration in the differential diagnosis of a cystic mass in any anatomic localization, especially in endemic areas. J Clin Exp Invest 2015; 6 (1): 75-77