Intralobar pulmonary sequestration is rare congenital lung disease characterized by a cystic portion of the lung that derives its arterial blood supply though aberrant vessel directly of systemic circulation. Intralobar pulmonary sequestration is usually contained within the visceral pleura of a pulmonary lobe and its venous drainage to the pulmonary venous system. We experienced a case of pulmonary sequestration postoperatively confirmed. The patient was 48-year-old female whose complaints were cough and left chest pain. Chest film showed large homogenous opacity in left lower lung field. By operation, adult fist sized mass at the lower lobe were noted. An aberrant artery, measuring 1.0 cm. in diameter and 2.0 cm. in length, arose from the descending thoracic aorta just above the diaphragm. The anomalous systemic artery was ligatures and resection, and associated with left middle, lower bilobectomy was done. The postoperative course was uneventful, and 10 days later discharged.