Glycosylation modification plays an important role in the regulation of solubility, stability and biological activity of various small molecules. Based on transcriptome data, we cloned two glycosyltransferase genes from tartary buckwheat and expressed them in E. coli. The result showed that: (1) the cDNA sequences of FtUFGT4 and FtUFGT5 were 1 434 bp and 1 470 bp in length, respectively. Both of their coding proteins were classifieds E group of AtUFGTs from Arabidopsis thaliana, which may be involved in flavonoid glycosylation. (2) Multiple sequence alignment indicated that there was a PSPG Box at their Cterminal, and the catalytic activity site was H16 and H17, respectively. Meanwhile, both of them had a typical GTB structures in plant glycosyltransferase. Moreover, the molecular docking results exhibited that FtUFGT4 and FtUFGT5 could dock with cyanidin and UDP. (3) FtUFGT4 and FtUFGT5 were ectopic expressed in the E.coli solubly. The thin layer chromatography (TLC) proved that they showed the cyanidin 3Oglucoside activity.