In order to investigate the toxicity of rutin-rich dough from the Tartary buckwheat variety ‘Manten-Kirari,’ acute and subacute toxicity studies (10,000 and 5,000 mg/kg flour, respectively) were performed using rats. In the acute toxicity study, no toxic symptoms were observed and no rats died during the test. Body weight in the ‘Manten-Kirari’-treated group was not significantly different when compared with that of the control group. On pathologico-anatomic observation, no unusual symptoms were observed in the ‘Manten-Kirari’-treated group when compared with the control group. In the subacute toxicity study, no toxic symptoms were observed and no rats died during the test. Body weight and food intake in the ‘Manten-Kirari’-treated and common buckwheat groups were not significantly different when compared with the control group. However, some investigated properties, such as urine protein and serum albumin, were significantly different in the ‘Manten-Kirari’ and common buckwheat groups when compared with the control group. However, these changes were not caused by toxicity, but by transient changes. On pathologico-anatomic observation, some abnormalities were observed in the liver, kidneys, heart, lung, bronchi and pituitary gland in some rats. However, the incidental rates in the ’Manten-Kirari’ and common buckwheat groups did not differ when compared to controls. Therefore, these abnormalities may be caused by natural generation. Based on these results, we concluded that dough at a dose of 5,000 mg flour/kg is at a non effect level.