Objective To investigate the changes and clinical significance of Treg and Th17 cells in patients with ovarian endometrioma (OEM) pre-and post-laparoscopy.Methods 36 patients with OEM undergoing laparoscopic surgery and confirmed by the pathology were enrolled as the experiment group,and 25 patients with fallopian tube obstruction who received laparoscopic examination were enrolled as the control group.The peripheral blood samples were collected from the control group and the experiment group before operation as well as from the experiment group 3 months after operation.Intraoperative peritoneal fluid were also collected from both groups.The levels of IL-17,IL-22,IL-23,IL-10 and TGF-β in serum and peritoneal fluid were detected by ELISA.The proportion of Treg and Th17 cells in peripheral blood was detected by flow cytometry.Results Compared with the control group,the levels of IL-17,IL-22 and IL-23 in the peritoneal fluid and serum of the experiment group increased significantly,while the levels of IL-10 and TGF-β were significantly decreased (P＜0.05).The proportion of Th17 cells in the peripheral blood of the experiment group increased significantly,and the proportion of Treg cells decreased significantly (P＜0.05).Compared with pre-laparoscopic treatment,the serum IL-17,IL-22 and IL-23,and the proportion of Th17 cells in peripheral blood were significantly decreased in the experiment group,and the levels of IL-10 and TGF-β in serum increased significantly (P＜0.05).Conclusions In patients with OEM,Treg and Th17 cell imbalance and the expression of related cytokines in disorder may be an important factor in the occurrence and development of disease.Detection of Treg/Th17 cells and their cytokines plays an important role in evaluating the severity of the disease and judging the efficacy of laparoscopic treatment and prognosis of OEM.