Breast cancer is the most pervasive cancer tormenting women, with increasing incidence and mortality rates year after year. MicroRNAs (miRNAs) with abnormal expression has various effects in biological processes and progression in diverse tumors. Nevertheless, it is vitally crucial for us to inspect more underlying molecular mechanisms for the therapy of patients with breast cancer. In the paper, we inquired the expression level and potential regulation mechanism of miR-374c-5p in breast cancer. Our research found out that miR-374c-5p was low-level expressed in breast cancer. Upregulation of miR-374c-5p repressed cell proliferation, migration, and also epithelial-mesenchymal transition (EMT), and induced cell apoptosis of breast cancer cells. Further, we concluded that miR-374c-5p interacted with TAF7 and downregulated its expression. Moreover, miR-374c-5p modulated DEP domain containing 1 (DEPDC1) through mediating TAF7. Finally, rescue assays represented that miR-374c-5p suppressed breast cancer development via TAF7-mediated transcriptional regulation of DEPDC1. We uncovered that overexpressed miR-374c-5p inhibited the development of breast cancer via TAF7-regulated transcriptional regulation of DEPDC1, which may be a novel and vital proportion of cancer diagnosis and treatment strategies.