A partial anomalous pulmonary venous connection (PAPVC) is an uncommon congenital anomaly which is frequently associated with congenital heart disease such as an atrial-level shunt. This report documents the case of an 81-year-old man with PAPVC which was incidentally discovered during a right upper lobectomy for lung cancer. Surgery was performed through a minithoracotomy of an auscultatory triangle using a video-assisted procedure (video-assisted thoracic surgery: VATS). Although the ramus lobi medii was connected normally, the right superior lobe vein was found to drain into the superior vena cava. The surgery was successful, and the patient had an uneventful postoperative course. Asymptomatic PAPVC without an atrial septal defect (ASD) is extremely rare. If the PAPVC is located in a different lobe, a pulmonary resection for lung cancer would precipitate an adverse outcome without a correction of the PAPVC. Surgeons should therefore be cautious regarding the potential existence of a PAPVC when a patient undergoes surgical procedures, especially VATS, for lung cancer.