Abstract: In order to study the relation-ship between expression level of Bmlipase-1 and resistance level of silkworm to BmNPV,we took the resistance varieties KNC and sensitive varieties HYB and the hybrid strains of two varieties as materials.Detected the resistance to BmNPV and its corresponding lipase (Bmlipase-1) gene expression level by virus( BmNPV) attack test and fluorescent quantitative PCR(qRT-PCR)technology.The results showed that is consistent with the level of expression of Bmlipase-1 and the strength of resistance. The expression level was higher in silkworm varieties with stronger viral resistance, otherwise it is lower. The expression level of Bmlipase-1 had significant differences between KNC and HYB; After infection by BmNPV ,the expression of Bmlipase-1 in silkworm strains KNC, KNC × HYB and HYB ×KNC was significantly higher than that of non-infection by BmNPV, However, HYB only had trace amounts of regulated changes. It’s as one of bases in select anti-BmNPV material in the process of the silkworm breeding.