Abstract: Objective：To investigate the effect of the different modes of one lung ventilation (OLV) on the changes of inflammatory factors and oxygen free radicals in patients undergoing esophagectomy. Methods：40 patients with esophageal cancer undergoing esophagectomy were randomly divided into two groups: long time of OLV group (groupⅠ) and intermittent two lung ventilation (group Ⅱ). Blood samples were collected after induction of anesthesia(T₁), at OLV 45 minutes(T₂), OLV 90 minutes(T3) and 2 hours after operation (T₄) for detecting TNF-α, IL-6, IL-8, MDA and SOD concentrations, respectively. Results：Serum TNF-α, IL-6 and IL-8 concentrations were all significantly increased at T₂ (P<0.05）. Serum TNF-α, IL-6 and IL-8 concentrations were lower at T_3-4 in group Ⅱ than those in groupⅠ (P<0.05）.Meanwhile, serum MDA concentration was obviously higher in T_3-4 (P<0.05 ）than that in T1 of both groups, and lower at T_3-4 in group Ⅱ than that in groupⅠ(P<0.05）.Serum SOD concentration was dramatically lower in T_3-4 (P<0.05）than that in T1 of both groups, and higher at T_3-4 in group Ⅱ than that in group Ⅰ(P<0.05）. Conclusion ：Intermittent two lung ventilation could alleviate the injury of lung during OLV through inhibiting the generation of oxygen free radicals and the release of inflammatory factors.