Abstract: Objective:To explore the value of high frequency color Doppler ultrasound(HCDFI) in the diagnosis of breast duct atypical hyperplasia and early breast ductal carcinoma.Methods:Ninety female patients with breast examination were detected using HCDFI,and divided into the breast duct atypical hyperplasia group(45 cases,ADH group) and early breast ductal carcinoma(45 cases,DCIS group) according to the result of pathology.Forty-five patients with general ductal hyperplasia were set as the UDH group.The image characteristics between three groups were compared.Results:With the progress of disease in UDH group,ADH group and DCIS group,the boundary regularity and clarity of lesions decreased gradually,the low echo attenuated,the high echo halo increased,and the blood flow around the lesions increased gradually(P<0.01).Conclusions:The HCDFI examination can best diagnose the breast disease,the cost of which is low,and which can be promoted as a routine examination.