Objective To investigate the effect and clinical characteristics of the treatment of adenomyoma and adenomyosis of Uterus by radiofreuqency heat coagulation minimal invasive treatment (RHCMIT). Methods One hundred and seventy-eight patients (122 with adenomyoma less than 5 0 cm in diameter and 56 with adenomyosis) with severe dysmenorrhea, were treated by RHCMIT. A special heat-coagulator were placed to the lesion through vaginal and uterine cavity, monitored by B ultrasound, in order to heat-coagulate the lesion by raising the local temperature to 60~80℃. Results By the clinical and B ultrasonic examination, the average diameter of the adenomyomas in this group was 3 9 cm and the average thickness of adenomyosis uterine wall was 4 0 cm. The dysmenorrhea releasing rate was 93 3% in adenomyoma and 96 4% in adenomyosis in 18-month follow up. Conclusions RHCMIT is a mini-invasive, safety, fast, effective and low-cost therapy for adenomyoma less than 5 0 cm in diameter and adenomyosis of uterus.