Flavonoids are important functional components of tartary buckwheat, and its glycosylation modification can change the stability, solubility and biological activity of flavonoids in organisms. Based on the analysis of transcriptome data of tartary buckwheat, we cloned the tartary buckwheat flavonoid glycosyltransferase (UDPglycose: flavonoid glycosyltransferase, UFGT) gene FtUFGT1 with RTPCR using the total RNA extracted from tartary buckwheat leaves. The recombinant expression vector was constructed by seamless cloning method and transformed into E.coli Rosetta (DE3) competent cell. The recombinant expressed protein was purified by GSTresin, and the catalytic properties of purified FtUFGT1 were analyzed by high performance liquid chromatography (HPLC). The results showed that: (1) the cloned FtUFGT1 coding region was 1 413 bp, which encodes 470 amino acids, and the recombinant expression vector pGEX6P1FtUFGT1 was successfully constructed. (2) The tartary buckwheat FtUFGT1 gene expressed soluble protein in E.coli Rosetta (DE3), and highpurity FtUFGT1 was purified by GST affinity chromatography. (3) HPLC analysis showed that tartary buckwheat FtUFGT1 could catalyze the synthesis of isoquercetin with quercetin as the substrate, with a specific activity of 9.174 U/mg; the optimum temperature of recombinant FtUFGT1 is 30 ℃, and the optimum pH is 7.0. In addition, 5% (V/V) methanol and 0.5% (V/V) Triton X100 could significantly inhibit its activity. These results laid the foundation for further revealing the biological function of FtUFGT1 and catalyzing the synthesis of flavonoid derivatives in vitro.