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The programmed cell death protein 1(PD-1)/programmed death-ligand 1(PD-L1) signaling pathway is a key mechanism underlying tumor immune escape. It suppresses anti-tumor immune responses through various mechanisms, including T-cell exhaustion, expanding regulatory T cells(Tregs), promoting M2 macrophage polarization, inhibiting natural killer(NK) cell function, and disrupting the balance of glycolysis/fatty acid oxidation metabolism. Immune checkpoint inhibitors(ICIs) targeting the PD-1/PD-L1 pathway have shown significant efficacy in the treatment of solid tumors. However, approximately 60%-70% of patients do not benefit due to drug resistance or immune-related adverse events(irAEs), and the heterogeneity of the tumor microenvironment(TME) further limits their effectiveness. Single-target blockade strategies are insufficient to comprehensively reverse immune escape, which highlights the urgent need for multidimensional interventions. Numerous studies have shown that various TCM active ingredients and compounds can regulate the PD-1/PD-L1 pathway through multiple targets to enhance immune responses. Their mechanisms involve modulating key signaling pathways, mediating epigenetic changes, reprogramming cellular metabolism, and reshaping the immunosuppressive microenvironment. Therefore, this review, focusing on the PD-1/PD-L1 pathway, systematically summarized the research progress on TCM active ingredients, compounds, and patent medicines in cancer immunotherapy. It aims to analyze their immunoregulatory networks, providing theoretical insights and translational directions for optimizing cancer immunotherapy strategies.