The optimal location to insert a chest tube for postoperative drainage has not been identified. We performed a retrospective equivalence study to identify whether the efficiency is similar regarding anterior or posterior position of chest tube in thoracic cavity after video-assisted thoracoscopic surgery for non-small-cell lung cancer.A retrospective review of 4263 patients undergoing non-small-cell lung cancer resection from October 2009 to August 2019 in the Western China Lung Cancer Database was conducted. Propensity score matching was performed to balance baseline characteristics between anterior and posterior groups. Chest tube duration, drainage volume, postoperative complications and hospitalization cost were compared. Equivalence margin was defined as (-1, 1) in 95% confidence interval of the mean difference of chest tube duration.After propensity score matching, we investigated 2912 patients with anterior or posterior (1456 vs 1456) chest tube location following lung cancer resection. The mean time to chest tube removal was 3.39 days in the anterior group and 3.38 days in the posterior group (P = 0.52), while the mean difference and 95% confidence interval were 0.02 (-0.17, 0.20). The mean postoperative hospital stays in 2 groups were 5.47 vs 5.24 days (anterior vs posterior, P = 0.02). No significant differences were identified regarding the drainage volume during the first 3 postoperative days, postoperative complications and hospitalization cost.The comparison of clinical outcomes between anterior and posterior location of chest tube met the criteria for equivalence. For lung cancer patients undergoing video-assisted thoracoscopic surgery resection, it was free choice on anterior or posterior single-tube insertion.© The Author(s) 2022. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.