Abstract: Two new polypeptides named RGPI and RGPII were isolated from the Chinese drug red ginseng for the first time. They were identified as propadecopeptide and pentadecopeptidex on the basis of analysis of amino acid composition and determination of molecular weight. Further-more. the effects of RGPs on the content of polysaccharides and the activity of succinodehydrogenase in the 2BS cells of the lung of human embryo were studied.