In this study,the biological activity of lectin PCL-2 of Polygonatum cyrtonema on human prostate cancer LNCap cells and its possible anti-tumor mechanism were explored.PCL-2 was extracted and isolated from P. cyrtonema fresh medicinal materials,and LNCap cells were cultured in vitro.WST-1 and colony formation experiments were used to detect the proliferation of LNCap cells.The level of ROS in LNCap cells were determined by 2,7-dichlorofluorescein yellow diacetate (DCFH-DA) fluorescence probe method.The expression levels of related genes and proteins in LNCap cells was measured by qRT-PCR and Western blot.Activity study results show that PCL-2 can significantly inhibit the proliferation of LNCap cells,promote the generation of ROS in cells.Mechanism research results show that PCL-2 induces LNCap cells apoptosis by up-regulating the mRNA expression levels of Bax,Caspase-3 and Caspase-9 genes and proteins and down-regulating the mRNA expression levels of Bcl-2 genes and proteins.The results of this study show that PCL-2 has a significant effect in inducing apoptosis of LNCap cells,and it can be used as a potential drug for inhibiting prostate cancer.