The gp37 genes of Spodoptera litura NPV (SpltMNPV) was cloned and sequenced. Employing computer analysis, glycosilated sites and the promoter motif existed in the gp37 gene. and was shown as a late gene encoding a 37 ku glycoprotein. A phylogeny tree was designed by the comparison of their homologues from known gp37 genes of baculoviruses. It was shown that the phylogeny of baculoviruses on the basis of gp37 gene was different from that based on polyhedrin genes. For example, Bombyx mori NPV (BmNPV) and Autographa californica NPV(AcMNPV) were evolved in the same branch, otherwise, they were put in two distinct branches in the tree according to the analysis of polyhedrin. This result was consistent with the baculovirus phylogeny based on EGT published previously.