Abstract: Objective To investigate characteristic imaging manifestation of ductal carcinoma in situ(DCIS)and the advantages of mammography combined with enhanced magnetic resonance imaging(MRI)in diagnosing DCIS. Methods Imaging results of 45 patients undergoing surgery and confirmed as DCIS and DCIS with small invasive foci were retrospectively reviewed in our study. The imaging manifestations of DCIS in mammography and enhanced MRI were analyzed, and diagnostic efficacy of mammography combined with enhanced MRI in diagnosing DCIS was evaluated. Results Mammograms findings of DCIS showed calcification in 28 cases(28/45, 62.2%), including clustered calcification in 12 cases(12/28, 42.9%)and segmental calcification in 13 cases(13/28, 46.4%), and regional distribution calcification in 3 cases(3/28, 10.7%). Enhanced MRI findings showed that there were 33 cases(33/45, 73.3%)with non-mass enhancement, and the distribution patterns included segmental enhancement in 11 cases(11/33, 33.3%), linear enhancement in 10 cases(10/33, 30.3%), focal enhancement in 9 cases(9/33, 27.3%)and regional distribution enhancement in 3 cases(3/33, 9.1%). The internal enhancement patterns of non-mass enhancement included clumped pattern in 18 cases(18/33, 54.5%), heterogeneous enhancement in 13 case(13/33, 39.4%), homogeneous enhancement in 2 cases(2/33, 6.1%)and clustered ring enhancement in 21 cases(21/33, 63.6%). The accuracy rates of mammography, enhanced MRI and their combination in diagnosis of DCIS were 53.3%, 71.1% and 86.7%, and there were statistically - significant differences in accuracy rates(P<0.05). Conclusion Clustered or segmental calcification in mammograms, segmental or linear enhancement with clumped internal architecture and clustered ring enhancement in enhanced MRI are the characteristic imaging manifestations of DCIS. The combination of mammography and enhanced MRI could achieve mutual complementarity and improve the diagnostic accuracy of DCIS.