Objective To investigate the relationship between oxidative stress level and endometrium receptivity in endometriosis (EMS) related infertility and its effect on pregnancy outcome in assisted reproduction. Methods A total of 106 patients with EMS-related infertility who received in vitro fertilization-embryo transfer (IVF-ET) assisted pregnancy in our hospital from January 2021 to February 2024 were selected as the study objects. According to the pregnancy outcome of IVF-ET, the patients were divided into a successful group (n=57) and a failed group (n=49). The endometrial receptance and oxidative stress levels of the two groups were compared, and the correlation between oxidative stress indexes and pregnancy failure of the endometrial receptance and EMS related infertility patients with IVF-ET was analyzed by Logistic regression.Results There were significant differences in endometrial type and endometrial blood flow distribution between the two groups (P<0.05). There was a significant difference in endometrial receptivity between the successful and failed groups (P<0.05). The levels of ROS and 8-iso-PGF2 α in the successful group were significantly lower than those in the failed group; The levels of GSH Px and PON-1 in the successful group were significantly higher than those in the failed group (P<0.05), and the levels of 8-iso-PGF2α(β=0.742, 95%CI: 0.342~1.142), ROS(β=-0.709,95%CI: -1.078~〖CD*3/5〗0.341), GSH-Px(β=1.462, 95%CI: 0.952~1.971) and PON-1(β=-0.375, 95%CI:-0.605~ -0.146) were independently correlated with pregnancy failure (P<0.001). Among them, ROS had the highest AUC (0.874) in predicting IVF-ET pregnancy outcomes in EMS related infertility patients, and its sensitivity, specificity and accuracy were 0.912, 0.793 and 0.853, respectively. The levels of 8-iso-PGF2α, ROS, GSH-Px and PON-1 were significantly correlated with various endometrial receptivity indexes (P<0.05). Endometrial type, endometrial thickness, endometrial blood flow distribution, RI, PI and mean blood flow velocity were significantly mediating the relationship between oxidative stress level and IVF-ET pregnancy outcomes in EMS related infertility patients (P<0.001).Conclusion The oxidative stress level of EMS-related infertility patients is closely related to the pregnancy outcome of IVF-ET, and ROS is effective in predicting pregnancy failure of IVF-ET. There is a certain correlation between oxidative stress level and endometrial receptivity. Endometrial receptivity in patients with EMS related infertility may be an important mediating regulatory factor for the effect of oxidative stress level on the pregnancy outcome of IVF-ET