Objective:To analyze the influencing factors of ultrasound-guided anhydrous ethanol interventional therapy in the treatment of ovarian endometriosis cyst(OEC).Methods:The clinical data of 109 patients with OEC were retrospectively analyzed.Ac-cording to the cyst volume reduction rate and symptom relief status at 6 months after treatment,the patients were divided into effective group(cyst volume reduction ≥ 50％and significant symptom improvement,n=82)and ineffective/partially effective group(cyst vol-ume reduction＜50％or not significant symptom improvement,n=27).Univariate and multivariate Logistic regression analyses were used to screen the influencing factors of the efficacy.Results:Univariate analysis showed that age,cyst diameter,cyst wall thickness,number of cysts,loculated cyst,side of cyst,history of endometriosis surgery,uterine fibroids or infertility,postoperative gonadotropin-re-leasing hormone agonist(GnRH-a)use,postoperative residual mass and preoperative serum CA125 level were related to efficacy(P＜0.05).Multivariate Logistic regression analysis suggested that age,cyst diameter,cyst wall thickness,loculated cyst,cyst side,postoper-ative residual mass and preoperative serum CA1 25 were independent risk factors,while postoperative GnRH-a use was a protective fac-tor(P＜0.05).Conclusion:Older age,thick cyst wall thickness,loculated cyst,postoperative residual mass and elevated preoperative serum CA125 level are risk factors affecting the efficacy of ultrasound-guided anhydrous ethanol interventional therapy for OEC.