Breast cancer has emerged as the primary cause of mortality stemming from malignancies among women. HuaChanSu has demonstrated efficacy in suppressing the progression of various malignancies. However, the specific immune targets and pathways influenced by HuaChanSu within mammary tumors remain elusive. This study is designed to uncover potent monomers and pivotal targets associated with HuaChanSu's anti-breast cancer Immunotherapy. The genes pertinent to HuaChanSu and breast cancer were acquired individually from publicly available databases. Interaction analysis using Cytoscape was conducted on common genes to determine the most suitable targets and crucial constituents of HuaChanSu's Immunotherapy against breast cancer. Following this, molecular docking was employed to validate ligand and receptor binding interactions. Lastly, the identified core genes underwent assessment of immune infiltration. The intersection of HuaChanSu and BC targets yielded a total of 49 differentially expressed genes. Bufalin emerged as the most potent constituent in Immunotherapy. Immunoassay data demonstrated significant correlations (r > 0.03, p < 0.05) between S100B, MMP9, FOS, EGFR, KIT, MME, and immune infiltration within BC. Molecular docking further corroborated the effective binding of Bufalin with immune-related genes. Through network pharmacological validation, we propose the extraction of Bufalin, a monomeric constituent of Huachansu, to exert immunomodulatory effects aimed at inhibiting the progression of breast cancer. Most of the target genes (S100B, BIRC5, MMP9, FOS, EGFR, KIT, and MME) are common targets for immunotherapy.