Abstract: Objective To investigate the clinical efficacy of levonorgestrel-releasing intrauterine system(LNG-IUS)in the treatment of adenomyosis.Methods Seventy patients with adenomyosis diagnosed according to clinical symptoms,magnetic resonance imaging(MRI)findings,laparoscopy and/or color-Doppler ultrasound imaging were treated with LNG-IUS,and the menstrual blood volume,dysmenorrhea,uterine volume,hepatic function and serum lipids were observed and evaluated.Results In the first month of treatment,the menstrual blood size was reduced significantly to(35±12)% of that before treatment(P<0.01),and further to(7±4)% in the twelfth month(P<0.01).The average uterine volume was decreased by 18.6%(P<0.05)after the treatment,and dysmenorrhea was obviously relieved or completely disappeared alleviated.The condition of anemia was also improved rapidly,and no obvious side-effects on hepatic function and serum lipids were observed.Conclusion LNG-IUS is an effective and safe therapy for adenomyosis.