OBJECTIVE： To investigate clinical efficacy and safety of goserelin in the treatment of adenomyosis complicated with severe dysmenorrheal before placing levonorgestrel intrauterine system （LIS）. METHODS： A total of 140 adenomyosis patients with severe dysmenorrheal were selected from Sanya Family Planning Technology Service Center during Jan. 2014-Jan. 2016， and then divided into control group and observation group according to lottery method， with 70 cases in each group. Both groups received LIS within first 7 d of menstruation， and observation group was given Goserelin acetate sustained-release implant 10.8 mg subcutaneously via anterior abdominal wall one week before placing. Therapeutic efficacy was evaluated 6 months later. The improvement of dysmenorrhea was compared between 2 groups. The uterine volume， COX dysmenorrhea score （CMSS）， menstrual volume， hemoglobin （Hb） and CA125 content were compared between 2 groups before and after treatment. The occurrence of ADR was also compared. RESULTS： The rate of dysmenorrheal improvement in observation group was 95.71％， which was significantly higher than 81.43％ of control group， with statistical significance （P＜0.05）. Before treatment， there was no statistical significance in above indexes between 2 groups （P＞0.05）. Compare to before treatment， CMSS score， menstrual volume and CA125 content of 2 groups were decreased significantly after treatment， while Hb content was increased significantly； the observation group was significantly better than the control group， with statistical significance （P＜0.05）. There was no statistical significance in uterine volume between 2 groups before and after treatment （P＞0.05）. There was no statistical significance in the incidence of ADR （10.00％ vs. 14.29％） between 2 groups（P＞0.05）. CONCLUSIONS： Goserelin in the treatment of adenomyosis complicated with severe dysmenorrheal before placing LIS can effectively relieve dysmenorrheal， reduce menstrual volume and improve Hb and CA125 levels， but do not increase the risk of ADR.