Objective To investigate the value of multi-slice spiral CT (MSCT) in the prediction of lung function after lung cancer surgery. Methods Patients with lung cancer who underwent selective pneumonectomy in thoracic surgery of the hospital from February 2017 to February 2018 were enrolled. All patients underwent MSCT scan and clinical lung function examination before and at 2 months after surgery. The lung volume measured by preoperative CT, forced expiratory volume in 1s (FEV1), forced vital capacity (FVC) and surgical resection range measured by lung function examination were performed to estimate postoperative FEV1 and FVC. And they were compared with FEV1 and FVC measured by postoperative lung function examination. The correlation was analyzed. Results There was no significant difference in FEV1 and FVC measured by preoperative MSCT and postoperative clinical lug function examination (P＞0.05). The postoperative FEV1 and FVC in patients with lung cancer predicted by MSCT were positive correlated with those measured by postoperative clinical lung function examination (r=0.912, 0.927, P＜0.05). Conclusion MSCT is of high predictive value in lung function after lung cancer resection, which can be used as a guiding tool of preoperative risk assessment for lung cancer resection.