Objective To investigate the effect of surgical intervention on IVF/ICSI assisted conception outcomes in patients with ovarian endometriosis （OEM）. Methods OEM patients who underwent IVF/ICSI treatment at the Reproductive Center of the Third Affiliated Hospital of Zhengzhou University between January 1， 2019 and February 1， 2024 were selected， including 228 cases in the non-operated group before assisted conception （Group A） and 426 cases in the operated group before assisted conception （Group B）， and the assisted conception outcomes of the two groups were analysed. Results There were no statistically significant differences in female age， BMI， infertility years， infertility type， and basal FSH level between the two groups （P > 0.05）. AMH level and basal AFC were higher in group A than in group B （P = 0.003）. There was no statistical difference in the application of ovulation induction programme， total number of Gn days and total amount of Gn between the two groups （P > 0.05）， but the amount of Gn initiation in Group A was lower than that in Group B （P = 0.011）. Applying multiple linear regression to adjust for confounding factors， there was a statistical difference in the 2PN fertilization rate between Groups A and B （P = 0.007）， whereas there was no statistical difference in the number of eggs obtained， the rate of available embryos， the rate of high-quality embryos and the rate of blastocyst formation between the two groups （P > 0.05）. After applying binary logistic regression to adjust for the influencing factors related to clinical pregnancy rate and live birth rate， the clinical pregnancy rate （aOR = -0.896， 95%CI： 0.540 ~ 1.488）， live birth rate in the two groups （aOR = 0.976， 95%CI： 0.589 ~ 1.620） remained statistically indistinguishable. Conclusions Surgical intervention may further impair ovarian reserve function in patients with OEM， but does not appear to affect embryo quality or pregnancy outcome. Surgical treatment prior to assisted conception may improve fertilization rates in patients with OEM.