Abstract: Objective To investigate the value of color doppler ultrasonography(CDUS) and digital mammography in diagnosis of breast ductal carcinoma. Methods CDUS and digital mammography results of 73 nidi from 73 patients diagnosed as DCIS by postoperative pathological results were retrospectively analyzed. The value of CDUS, digital mammography, separately and the combination in the diagnosis of DCIS were compared. Results Forty-eight nidi were diagnosed as DCIS. The sensitivity of CDUS and digital mammography was 66.67% (32/48) and 70.83% (34/48) respectively, there was no statistical signifi cance(P>0.05), and the specifi city was 90.32% and 80.65 % respectively, the positive predictive value was 91.43% and 85.00% respectively and the negative predictive value was 63.64% and 64.10% respectively. The sensitivity of the combination was 95.83% (46/48). The difference between the combination and CDUS or digital mammography alone had statistical signifi cance (P<0.05). Conclusion CDUS has higher detection rate in internal structure and peripheral duct disorder but lower detection rate in microcalcifi cation of DCIS than digital mammography. The combination could improve the accuracy of DCIS diagnosis.