Despite advances in prostate cancer treatment, castration-resistant prostate cancer (CRPC) remains clinically challenging due to inherent therapy resistance and a lack of durable alternatives. Although traditional Chinese medicine offers untapped potential, the therapeutic role of paeoniflorin (Pae), a bioactive compound derived from Paeonia lactiflora, in prostate cancer has yet to be investigated. Using an integrative approach (network pharmacology, molecular docking, and experimental validation), we identified Pae key targets, constructed protein-protein interaction networks, and performed GO/KEGG pathway analyses. A Pae-target-based prognostic model was developed and validated. In vitro and in vivo assays assessed Pae effects on proliferation, migration, invasion, apoptosis, and tumor growth. Pae exhibited potent anti-CRPC activity, inhibiting cell proliferation by 60% and impairing cell migration by 65% compared to controls. Mechanistically, Pae downregulated SRC proto-oncogene, non-receptor tyrosine kinase (SRC) mRNA expression by 68%. The Pae-target-based prognostic model stratified patients into high- and low-risk groups with distinct survival outcomes. Organoid and xenograft studies confirmed Pae-mediated tumor growth inhibition and SRC downregulation. Pae overcomes CRPC resistance by targeting SRC-mediated pathways, presenting a promising therapeutic strategy. Our findings underscore the utility of network pharmacology-guided drug discovery and advocate for further clinical exploration of Pae in precision oncology.