In this study, Polyphyllin G can potently induced apoptosis dependent on the activations of caspase-8, -3, and -9 and the changes of Bcl-2, Bcl-xL and Bax protein expression in different human NPC cell lines (HONE-1 and NPC-039). The gene discussed is CASP8; the disease is nasopharyngeal carcinoma.