Objective:To investigate the possible mechanism of Xieheyin in alleviating obese polycystic ovary syndrome with insulin resistance（PCOS-IR）and reducing inflammatory response. Method:Ten of sixty SPF femlae C57BL/6J mice were randomly selected as the normal group，and the rest mice were given letrozole 0.002 g·kg^-1 combined with fecal suspension 2 g·kg^-1 for 28 consecutive days to establish model of PCOS-IR.The mice that were successfully modeled were randomized into the model group，metformin group（0.25 g·kg^-1），and low（10 g·kg^-1），medium（20 g·kg^-1），and high-dose（40 g·kg^-1）Xieheyin groups，and administered with the corresponding drugs by gavage，once a day，for four consecutive weeks. Except the normal control group， the mice in the other groups were continuously given fecal suspension combined with letrozole solution to maintain the model during the treatment. The mice were weighed once a week.Levels of fasting blood glucose （FBG） were detected by blood glucose test strips.And enzyme-linked immunosorbent assay （ELISA） method was used to detect serum testosterone（T），follicle stimulating hormone（FSH），luteinizing hormone（LH），fasting insulin（FINS）level，and LH/FSH and Homeostasis model assesment of insulin resistance （HOMA-IR） were calculated．The uterus and ovaries were weighed and fixed.Hematoxylin-eosin（HE）staining was used to observe ovarian tissue pathology morphology. Western blot was used to detect the expression levels of tight junction key molecular zonula occludens 1（ZO-1），occludin in colon tissues，and the expression levels of Toll-like receptor 4/nuclear factor kappa B/Nod-like receptor protein 3（TLR4/NF-κB/NLRP3）signaling pathway and inflammation associated proteins cysteinyl aspartate specific proteinase-1（Caspase-1） and interleukin-1β（IL-1β） in colon tissues. Result:Compared with normal control group，the body weight of mice in the model control group increased significantly（P<0.01）. Serum FINS，FBG，HOMA-IR，T，LH/FSH were significantly increased（P<0.05，P<0.01）. The uterine organ ratio were decreased significantly（P<0.01），while the ovarian organ ratio were significantly increased（P<0.01）. The number of atresia follicles and cystic dilatation follicles increased significantly，and the number of corpus luteum significantly decreased，the thickness of follicular granulosa cells also decreased，while the white membrane thickness of the ovary increased. Tight junction related ZO-1，occludin proteins in colon tissues were all decreased（P<0.01）.The relative expression levels of inflammation-related protein IL-1β，Caspase-1 and TLR4/NF-κB/NLRP3 target protein signaling pathway were significantly increased（P<0.05）.Compared with model control group， the body weight of mice in the low，middle and high dose Xieheyin group decreased significantly（P<0.01）. The serum T，LH/FSH，FINS，FBG，HOMA-IR were significantly decreased（P<0.05，P<0.01）. The uterine organ ratio were increased（P<0.05），while the ovarian organ ratio were decreased（P<0.05）. The number of cystic follicles decreased and corpus luteum increased，the thickness of follicular granulosa cells increased and be arranged normally，while the white membrane thickness of the ovary increased slightly. The expressions of ZO-1，occludin proteins were increased（P<0.01）. The expression levels of IL-1β，Caspase-1 and TLR4/NF-κB/NLRP3 target protein in the high dose group were significantly decreased（P<0.01）. Conclusion:Xieheyin could activate intestinal TLR4/NF-κB/NLRP3 signaling pathway，inhibit pro-inflammatory factor secretion，improve obesity and IR，which was correlated with rebuilding intestinal mucosal barrier and inhibiting intestinal inflammation．