A novel human β3-galactosyltransferase gene β3GALT7 was isolated from human lung cDNA library and characterized. β3GALT7 is mapped to chromosome 19q13.2 by browsing the UCSC genomic database. It contains an ORF with length of 1 191 bp, encoding a protein with a signal peptide sequence and galactosyl-T domain, and its molecular mass and isoelectric point are predicted to be 43.3 ku and 8.37 respectively. The molecular mass of recombinant β3GALT7 protein expressed in prokaryote was coincide with the predicted. Northern blot showed that β3GALT7 was highly expressed in lung, throat and ileum, while the expression level was low in tongue, breast, uteri, testis. In addition, it was also demonstrated that β3GALT7 is differentially transcribed in human tumor cell lines.