Abstract: Using the DNA from PuGV-Ps (Pseudaletia unipuncta granulovirus propagated in the larvae of P. separata) as template, a 2.7 kb specific fragment was amplified by PCR reaction. Purified PCR product was cloned into plasmid pET-15b and a recombinant plasmid pET-15b-En was constructed. The PCR product was proved to be the full length gene encoding enhancin of PuGV-Ps by DNA sequencing. Sequence analysis revealed that enhancin gene from PuGV-Ps was tested to have 99.56% identity to that from PuGV, which was reported previously. Among the 11 mutation nucleotides, 7 of them concentrated in the 500 bp of 5' terminal half, while one was different within 500 bp in 3' terminal half. pET-15b-En vector was recombinanted into Escherichia coli BL21(DE3). When induced by IPTG, the protein with molecular weight 108 kD was expressed successfully. The protein expressed by the inserted foreign gene proved to be the target protein by Ni²⁺ column purification. It was promoted the target protein expression by adding 0.2 percent of glucose in the substrate. Bioassay showed that the extracted expressing protein had synergistic activity, enhanced the toxicity effect of delta-endotoxin of B. thruingiensis to larvae of H.armigera andS. exigua.