Abstract: Glycogen, such as glucose, fructose, galactose, xylose, are transported by sugar transporters across cell membrane and providing energy for organism. Using the reported amino acid sequences of sugar transporters in other organisms and silkworm scaffold and EST database, BmST1 gene homology to others in silkworm was obtained. The ORF is 1 392bp in length(GenBank accession number: FJ373021), the putative encoding protein contains 442 AA and the MW is 51.635KDa. The results of sequence analysis show that there is 2 exons and 11 transmembrane domain in gene. RT-PCR results indicate that gene is expressed only in the silk gland in all the tissues tested.