To investigate possible effects of buckwheat on blood glucose level and blood pressure, Sprague-Dawley rats were divided into two groups and fed either AIN-76 diet or modified AIN-76 diet with buckwheat flour for 4 weeks. At the end of experiment, determinations of blood pressure and blood glucose level(glucose tolerance test) were performed. In order to determine insulin levels in both fasted and glucose loaded serum, the animals in both groups were subdivided into two groups. Blood pressure was slightly decreased in the group fed buckwheat( 6mmHg) but not significantly. Glucose tolerance curve of the animal fed buckwheat flour showed clearly different pattern from that of the control group with decreasing tendency. Mobilization of serum insulin was 1.5 times faster in buckwheat group than in control group 1 hour after glucose loading. Further research is needed to find what substance(s) in buckwheat do this role.