Abstract OBJECTIVES We aimed to assess whether proximal ligation of the pulmonary vein stump (PVS) outside the pericardium reduces postoperative cerebral infarction (PCI) incidence after lobectomy. METHODS A single-institution retrospective review was conducted on 683 patients undergoing lobectomy for lung cancer, metastatic lung tumours, and benign diseases. Associations among PCI within 90 days, ligation of the PVS, and clinicopathological features were analysed. Effects of PVS ligation on PCI were assessed using multivariable regression. PVS length measured on three-dimensional computed tomographic angiography was compared between the non-ligation and ligation groups. RESULTS The non-ligation and ligation groups included 356 (January 2010 to March 2018) and 327 patients (April 2018 to November 2023), respectively. Seven non-ligation group patients (1.96%) underwent PCI (three in left upper lobectomy [LUL] and left lower lobectomy [LLL] and one in right lower lobectomy); no ligation group patients suffered PCI (p = 0.016). Univariable analysis showed that LUL, LLL, chronic kidney disease (CKD), heart failure, cardiovascular disease, and PVS ligation were significantly associated with PCI. Multivariable analysis demonstrated that PVS ligation (p = 0.034) was correlated with decreased PCI and LUL (p = 0.011), LLL (p = 0.010) and CKD (p = 0.004) with increased PCI. After ligation, PVS length was shortened in each lobe in a subset analysis of 109 patients. CONCLUSIONS Proximal ligation of the PVS outside the pericardium may be an option to prevent PCI in lobectomy. Patients with CKD and those undergoing left-sided lobectomy are at higher risk for PCI and may benefit from more intensive management.