The ecdysteroid UDP-glucosyltransferase (EGT) gene of Spodoptera litura multinucleocapsid nucleopolyhedrovirus (SpltMNPV), Guangzhouisolate was sequenced. The open reading frame of the gene is 1530 nucleotides long, encoding a putative protein of 509 amino acids with Mr of 58,500. The 5' noncoding region has a TATA box. A polyadenylation signal, AATAAA, is contained downstream of the translation stop codon. A putative signal peptide is present at the N-terminus of the protein. Homology comparison with other baculovirus egt genes showed that these genes are highly conserved. The SpltMNPV egt gene is closely related to that of Spodoptera littoralis nucleopolyhedrovirus (SliNPV) with the identities of 84% in nucleotide and 91% in amino acid, respectively. In this study, an alignment of amino acid sequences has been made and a tentative phylogenetic tree of twelve baculovirus egts is presented.