Abstract: Objective： To study the difference regarding differentiation of helper T lymphocytes(Th) between propofol anesthesia and sevoflurance anesthesia. Methods： A total of 60 patients, who received selective lumbar disc herniation surgery during Oct. 2010 and Jan. 2015, were selected and divided into two groups randomly, the propofol group which received total intravenous anesthesia with propofol and the sevoflurance group which received inhalation anesthesia with sevoflurance, with 30 cases in each. The non-invasive blood pressure, heart rate, pulse oxygen saturation, and end-tidal carbon dioxide partial pressure were monitored in all patients.Peripheral venous blood was sampled before and after anesthesia, before and after surgery, and one-day after surgery, respectively.The T cell expression on interferon-γ and interleukin-4, the percentage of Th1 cell and Th2 cell in peripheral blood, and the ratio between Th1 cell and Th2 cell were evaluated in each group. Results： There was no significant difference between the two groups regarding the non-invasive blood pressure, heart rate, pulse oxygen saturation, and end-tidal carbon dioxide partial pressure. The percentage of Th1 cell in peripheral blood in propofol group was significantly higher than that in sevoflurance group one-day after surgery(P< 0.05).There was no significant difference regarding the percentage of Th2 cell in peripheral blood between the two groups at different time point. The ratio between Th1 cell and Th2 cell in peripheral blood in propofol group was significantly higher than that in sevoflurance group one-day after surgery (P< 0.05). Conclusions： Compared with sevoflurance, propofol can preferably promote Th cell to differentiate into Th1 cell.Propofol may therefore have immunoprotective effect for patients during perioperative period.