Abstract: :Objective To investigate the inhibitory effect of flavonoids from morus folium on the nonenzymatic glycosylation.Methods The flavonoids from extracts of morus folium in different concenration(0.001,0.01,0.1μg/L)were added to a glycosylation system in vitro,and incubated for 1,4,7,14,21,28 days respectively,then the early glycasylation products were measured.Results The quantity of the early nonenzymatic glycosylation products had positive correlation with the incubating time,and each incresed significantly when the extracts added.Conclusion There was positive correlation between nonenzymatic glucosylation and incubating time in this system,and the falvonoids from morus foliuna may possess inhibitory effects on nonenzymatic glucosylation in vitro.