Abstract. It has been demonstrated that video-assisted thoracoscopic surgery (VATS) is feasible and safe in humans and animal models. The aim of the present study was to compare the surgical outcome using VATS with that of the standard transthoracic approach for pneumonectomy in dogs, to determine the acute-phase reaction in VATS pneumonectomy, and to analyze the difference between VATS and the standard transthoracic approach. A total of 14 dogs were divided into two groups (n=7); one group underwent VATS and the other group underwent a transthoracic pneumonectomy. Pre-, intraand post-operative physiologic parameters were monitored, in addition to the blood cell count and serum acute-phase protein (APP) concentrations. The APP and hemodynamic changes between the two approaches were analyzed. Mean surgical time in the VATS group (176.7 min) was significantly longer compared with the open group (132.4 min). All APP concentrations were significantly increased at day 1 postoperation and gradually decreased to preoperative concentrations. The serum concentration of C-reactive protein on day 3 and the white blood cell count on day 1 were significantly higher following surgery in the open group compared with the VATS group (P<0.05). No differences were observed in the physiological parameters between the two groups. Although VATS took longer, animals experienced smaller incision and less stress. Therefore, the VATS approach was satisfactory for total pneumonectomy.