Segmentectomy could be one of the standard modes of surgery for the treatment of early lung cancer. However, segmentectomy could be more difficult than lobectomy as to the management of inter-segmental plane. The relationship between methods of dividing an inter-segmental plane and postoperative complication/pulmonary function was investigated in this study. A retrospective study was conducted on 49 patients who underwent segmentectomy of the lung between February 2008 and April 2009 at our institute. Eighteen (36.7%) were male and 31 (63.3%) were female. The inter-segmental plane was divided with only a mechanical stapler in 18 patients, and electrocautery was used in the other 31 patients. There were no significant relationships between clinicopathological features and both procedures, except gender, operative time, and pleurodesis (P<0.05). Preserved forced expiratory volume in one second (FEV(1)) was not affected by the procedures. Patients who underwent left upper division segmentectomy had significantly more complications. On multivariate analysis, resected segment and intraoperative blood loss were found to be significant predictors for postoperative complications. There were no significant relationships between the methods of making inter-segmental planes and postoperative complications and/or lung functions. Resected segment and intraoperative blood loss were predictors for postoperative complication in segmental resection of the lung.