Objective：To investigate the learning curve of total thymectomy under subxiphoid process thoracoscopy and to summarize the technical points of the operation. Methods：The clinical data of patients undergoing total thymectomy from the beginning of October 2015 to October 2017 in our hospital were retrospectively analyzed. There were 21 males and 16 females. The cumulative sum analysis（CUSUM） analyzed the learning curve of total thymectomy under subxiphoid process thoracoscopy. Results：The average operation time was 123.7 min. The best fitting curve was cubic curve. The fitting equation was CUSUN（min）=89.703 7X-4.594 8X2 + 0.059 9X3（X is the number of operation）. Learning curve across the apex was observed in 13 cases. Taking 13 cases as the boundary，all cases were divided into A group and B group. There was no significant difference between the two groups in the operation time，but there were statistical differences in postoperative hospital stay，postoperative chest drainage tube placement time，postoperative complications between the two groups. Conclusion：In this study，13 cases are the lowest cumulative number of surgeries needed to span the learn－ing curve of total thymectomy under subxiphoid process thoracoscopy.