The patient was a female, admitted with “chronic cough and sputum for more than 10 years”. In October this year, she underwent thoracoscopic resection of a large pulmonary blister, 20cm*15cm. A 3-cm incision was made in the 5th intercostal space of the left anterior chest, and intraoperative exploration revealed a huge pulmonary blister in the basal segment of the left lower lung, with a wide base of the blister and no tilted connection with normal lung tissue. The postoperative pathological diagnosis: bronchopulmonary cyst. The cough and sputum symptoms improved significantly after the operation, and he was discharged from the hospital 5 days later. Giant pulmonary blister in the medial basal segment of the left lower lung with a wide base and no tilted connection with normal lung tissue Complete resection of pulmonary blister in the left lower lung, ready for removal from the chest, diameter >15 cm