Objective To discuss the surgical indication of mammotome （MMT） operation and its auxiliary diagnosis value on breast cysts. Methods Seventy-eight patients with breast cysts from May 2010 to November 2011 in this hospital were enrolled. Excision and biopsy were performed according to the following guidelines：Single cyst with inhomogeneous interna echoes and diameter at least 1 cm；Multiple cysts associated with irregular megalgia， localized thickening of breast or ineffective drug treatment after three months；High risk of breast cancer；Hypoechoic nodules and laticifers exaggerated cysts；Ultrasonography showed disorderly echo and abundant blood supply in glandular tissues around the lesions. The result of preoperative ultrasound was compared with that of postoperative pathology diagnosis. Results In these 78 breast cysts patients with preoperative ultrasound diagnosis， 40 cases were breast multiple cysts， 38 cases were multiple cysts plus untouchable hypoecho nodules；42 cases were high risk lesions， and the other 36 cases were low risk lesions. Postoperative pathology diagnosis revealed 27 cases of cystic hyperplasia， 2 cases of atypical hyperplasia， and 1 case of breast cancer in the ultrasonic high risk lesions， and 19 cases of cystic hyperplasia in the ultrasonic low risk lesions. Ultrasound diagnostic accuracy rate was 60.26%（47/78）， sensitivity was 61.22%（30/49）， and specificity was 58.62%（17/29）. The number of resection lesions was 13.00±8.16， the time of operation was （74.25±22.68） min. The average hospital stay was 1 d after surgery. The local hematoma occurred in 2 cases and no other complications occurred during one month of follow-up. Conclusions The guidelines of MMT protocoled according to clinical manifestation of breast cyst patients and imaging of high-frequency ultrasound in author’s department are simple and utility. Minimal excision and biopsy via MMT can confirm the histological type and help for early diagnosis of breast cancer and precancerous lesion. It is important and necessary to standardize the surgical indications of MMT in the clinical work.