Abstract: Objective: To assess the diagnostic value of digital breast tomosynthesis(DBT) combined with full field digital mammography(FFDM) in breast cancer.Methods: The imaging data of FFDM and DBT in 70 patients with breast cancer were retrospectively analyzed.The imaging results of the routine FFDM(craniocaudal position and mediolateral oblique position) were compared with the imaging results of FFDM combined with DBT.The lesions presentation,edge detail and peripheral sign in two groups were recorded,and the lesion was evaluated by mammographic report and BI-RADS.Results: The malignant lesions in 46 cases and bengin lesions in 24 cases were diagnosed using the routine FFDM imaging,and the coincidence rate of which in accordance with the results of pathology was 66%.The malignant lesions in 57 cases and bengin lesions in 13 cases were about diagnosed using the joint examination,and the coincidence rate of which in accordan-ce with the results of pathology was about 81%.The evaluation difference between two methods was statistically significant(P<0.05).Conclusions: DBT can improve the display and diagnosis efficiency of breast lesions,and early diagnosis level of breast cancer,which has good clinical significance.