Background: Pressure-regulated capacity control volume controlled (PRVC) ventilation mode is a new type of ventilation mode, which could reduce the occurrence of ventilator-related lung injury. The aim of this study was to explore PRVC mode on airway pressure, oxygenation index, pulmonary inflammatory index and prognosis in patients with one-lung ventilation during pulmonary segmentectomy.Methods: Eighty ASA Ⅱ-Ⅲ Patients with moderate to severe pulmonary dysfunction, ready to receive segmentectomy were randomly divided into VC and PRVC group, which included 40 patients in each group. PRVC ventilation mode was performed for patients in VC-group in the first 5 minutes after OLV, and then ventilation mode was transformed into VC ventilation mode till the end of operation. In PRVC-group, ventilation modes were performed in opposite order. The changes of airway peak pressure, airway platform pressure, pulmonary static compliance, blood gas analysis results and hemodynamics in the two groups under different ventilation modes were recorded. The whole blood samples and bronchoalveolar lavage fluid (BALF) in ventilated lung were collected to determine the level of TNF-α, IL-1β, IL-6 and IL-8 after the surgery. Results: Both static lung compliance and the peak expiratory pressure in PRVC-group were significantly lower than those in VC-group (P=0.023). But there were no difference in hemodynamic parameters such as heart rate, blood pressure. The arterial blood gas analysis (pH, pO2 and pCO2) between the two groups during, as well as postoperative pulmonary complications and length of hospital stay also did not show difference. However, the levels of TNF-α, IL-6, IL-8 and IL-10 in BALF in VC-group were significantly higher than that in PRVC-group (P=0.01). Conclusion: PRVC ventilation mode during intraoperative one-lung ventilation can effectively relieve airway pressure and reduce the secretion of inflammatory factors in the lung, which is a safe and protective ventilation mode for patients with poor preoperative pulmonary function who undergo pulmonary segmentectomy.