Objective To compare the effect of the different operation for mammary duct fistula (MDF). Method The clinical data of 85 cases of MDF were analysed retrospectively. Continuous section examinations between the multiple fistula was performed in 3 cases undergoing breastectomy.Results Among the 85 cases with 146 MDF, the opening located within 5cm around areola in 129 cases. MDF incision was performed on 38 cases, 34 cases cured, 4 cases recurred;MDF resection was performed in 44 cases, all the 44 cases were cured;simple mastectomy was performed on 3 cases of extensive breast inflammation,all the 3 cases cured. Conclusions Most of MDF occurs in main mammary duct. Most of the opening of MDF are around the areola. MDF incision or resection is the first choice of operation.