Objective: Study the influence of polygonatum sibiricum polysaccharide(PSP)on the life spans of silkworm.Methods: The silkworms were used as experimental objects which were hatched at the same time and have got through their dormant period thrice.They were divided into 5 groups:control group,high(2%) PSP dose group,middle(1%) dose group,low(0.5%) dose group and vitamine E(0.5%) applied group.The liquid medicine were sprayed on the surface of fresh leaves of mulberry for each group which were used as silkworms' feed.The medicine were provided 3 times after the fourth dormant period of the silkworms and 6 times after the fifth dormant period of the silkworms.Results: The high,middle and low PSP dose can prolong the silkworms' life span of larva-period,female chrysalis-period and female moth-period to different extent,can lighten the weight of larva silkworm,strengthen the resistivity of starvation of five-age larva silkworm.The effect of PSP is the same as vitamine E.Conclusion: PSP is the important anti-aging active site of polygonatum sibiricum redoute.It is worth studying further.