Abstract: Objective: To evaluate circulating miR-193 cluster as a biomarker for diagnosis of breast cancer (BC). Methods: A total of 130 BC patients and 45 healthy controls (HCs) were enrolled. The level of miR-193 cluster was analyzed by using GEO database. RT-qPCR was used to evaluate the level of miR-193 cluster in serum of participants. Receivers operating characteristic (ROC) curve analysis was manipulated to investigate their diagnostic value for BC. Results: In the screening stage, the results of GEO database indicated the expression of miR-193a-5p and miR-193b were decreased in the serum of BC patients with prior diagnostic value, and the significant decreased expressions of miR-193 cluster members, miR-193a-3p, -5p and miR-193b-3p, were observed in serum of BC patients compared with those in healthy controls by the determination of RT-qPCR（all P ＜0.01）. In the validation stage, the AUC^ROC of miR-193a-5p and miR-193b-5p were 0.888 (95% CI :0.808-0.969) and 0.954 (95% CI :0.902-1.000), respectively. In addition, the combined AUC^ROC of these two miRNAs was 0.982 (95% CI :0.966-0.999). Conclusion: miR-193a-5p and miR-193b-5p in serum could be served as diagnostic biomarker for screening of breast cancer, and the combined detections of the two miRNAs may exhibit more diagnostic efficiency and good clinical application potential.