ObjectiveTo investigate the mechanism underlying the effects exerted by the Qizhu prescription (QZP) in breast cancer (BC), and the respective targets. MethodsExpression data from the ArrayExpress and The Cancer Genome Atlas (TCGA) were used to identify differentially expressed genes (DEGs) in BC. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed on the DEGs to identify genes involved in protein–protein interactions. Molecular docking was used to explore the dynamic relationship between active molecules and targets. Cell function experiments and animal studies were conducted to evaluate the effects of hub genes and active QZP compounds on BC cell behavior. ResultsAmong the 25 evaluated BC-related targets of QZP, matrix metalloproteinase-1 (MMP1) and epidermal growth factor receptor (EGFR) exhibited the highest degrees of dysregulation. GO and KEGG enrichment analyses revealed that the anti-BC targets of QZP primarily affected drug responses and pathways in cancer cells. Molecular docking analysis suggested potential interactions between EGFR and quercetin/luteolin, as well as between MMP1 and luteolin/kaempferol/quercetin. Quercetin significantly reduced BC cell proliferation, migration, invasion, and tumor development in vivo. Treatment of BC cells with quercetin decreased the expression or activation of several associated proteins. ConclusionThe findings of our study provide new insights into the therapeutic potential of traditional Chinese medicine against BC, with particular reference to QZP.