ObjectiveTo explore the mechanisms of Yangjing Tongluo prescription （YJTL） in the treatment of intrauterine adhesion （IUA） from the perspective of oxidative stress mediated by the Kelch-like ECH-associated protein 1/nuclear factor erythroid 2-related factor 2/heme oxygenase-1 （Keap1/Nrf2/HO-1） signaling pathway. MethodsA total of 48 rats with normal estrous cycles were selected and randomly divided into a normal group （n=8） and a modeling group （n=40）. An IUA rat model was established using a dual-injury method combining surgical curettage and infection. Eight rats were randomly selected from the modeling group for a pilot experiment to confirm successful model establishment. After successful modeling， the remaining 32 rats were randomly divided into a model group， a low-dose YJTL group （YJTL-L）， a high-dose YJTL group （YJTL-H）， and a Progynova group. Rats in the normal and model groups were administered purified water （15 mL·kg^-1） by gavage daily， while rats in the YJTL-L， YJTL-H， and Progynova groups received YJTL at doses of 6.43 and 12.86 g·kg^-1 and Progynova at 2.06 × 10^-4 g·kg^-1， respectively， for 14 consecutive days. The general condition， uterine morphology， and uterine index of the rats were monitored. Histopathological changes in uterine tissue were observed using hematoxylin-eosin （HE） staining. Serum levels of reactive oxygen species （ROS） and glutathione peroxidase （GSH-Px） were measured by enzyme-linked immunosorbent assay （ELISA）. Protein expression levels of Keap1， Nrf2， and HO-1 in endometrial tissue were detected by Western blot. Immunofluorescence （IF） was used to assess the distribution of Nrf2 and HO-1， as well as the expression of Nrf2 in the cytoplasm and nucleus. ResultsCompared with the normal group， rats in the model group exhibited poor mental status and reduced mobility， markedly edematous and tortuous uterine morphology， decreased gland number， and inflammatory reactions in the endometrium， along with an increased uterine organ index （P<0.05）. Serum ROS levels were significantly increased （P<0.05）， while serum GSH-Px levels were significantly decreased （P<0.05）. In endometrial tissue， Keap1 protein expression was increased （P<0.05）， whereas Nrf2 and HO-1 protein expression was decreased. Mild nuclear translocation of Nrf2 was observed， accompanied by increased relative fluorescence intensity of nuclear Nrf2 and decreased relative fluorescence intensity of cytoplasmic HO-1. Compared with the model group， all treatment groups showed varying degrees of improvement in the above symptoms and pathological changes. Serum ROS levels were reduced （P<0.05）， serum GSH-Px levels were increased （P<0.05）， Keap1 protein expression in endometrial tissue was decreased， and Nrf2 and HO-1 protein expression was increased in a dose-dependent manner （P<0.05）. Notably， significant nuclear translocation of Nrf2 was observed， with correspondingly increased relative fluorescence intensity of nuclear Nrf2 and enhanced relative fluorescence intensity of cytoplasmic HO-1. ConclusionYJTL may enhance antioxidant capacity and repair oxidative damage to the endometrial basal layer by regulating the Keap1/Nrf2/HO-1 signaling pathway.