Objective To investigate the effect of probiotics in the adjuvant treatment of endometriosis(EMs)and its impact on intestinal flora diversity.Methods A total of 126 EMs patients treated from August 2019 to August 2021 were se-lected and divided into CG group and EG group according to random number table method,with 63 cases in each group.CG group was treated with Mifepristone tablets,and EG group was treated with compound Lactobacillus Acidophilus tablets based on CG group.The clinical efficacy of the two groups was compared,and the uterine hemodynamics,endometrial thickness,serum inflammatory factors,immune function markers,and intestinal flora diversity before and after treatment were analyzed in the two groups.In addition,the pregnancy status of patients with pregnancy needs was analyzed.Results After treatment,the total effective rate of EG group(93.65%,59/63)was higher than that of CG group(79.37%,50/63)(P<0.05).Af-ter treatment,pulsatility index(PI)and resistant index(RI)levels of uterine artery and endometrial thickness in the two groups were lower than those before treatment,and lower in EG group than in CG group(P<0.05).After treatment,the ser-um levels of tumor necrosis factor-α,interleukin-8 and interleukin-6 in the two groups were lower than those before treatment,and lower in EG group than in CG group(P<0.05).After treatment,NK cells and CD8+levels in the two groups were higher than those before treatment,which were higher in EG group than in CG group(P<0.05),while CD4+/CD8+and CD4+were lower than those before treatment,which were lower in EG group than in CG group(P<0.05).After treatment,intestinal flora richness,Simpson evenness index and Shannon-Wiener diversity index in the two groups were higher than those before treatment,which were higher in EG group than in CG group(P<0.05).The pregnancy rate in EG group with preg-nancy needs was higher than that in CG group at 6 and 24 months after treatment(P>0.05).The total pregnancy rate of pa-tients with pregnancy needs in EG group(73.33%,22/30)was lower than that in CG group(42.86%,12/28)(P<0.05).There was no significant difference in the total incidence of adverse reactions between the two groups(P>0.05).Conclusion Probiotics have a synergistic and auxiliary effect in the treatment of EMs patients,which can regulate the diver-sity of intestinal flora,improve clinical cure rate,ameliorate clinical symptoms and immune function,reduce inflammatory re-sponse,and contribute to the prognosis of patients with pregnancy.