Abstract: OBJECTIVE： To investigate the subacute toxicity of a dietary supplement containing Cyclocarya paliurus and Fagopyrum tataricum in rats. METHODS： Wistar rats were randomly divided into four groups according to body weight，including three dosage groups of the dietary supplement (1.67，3.33 and 6.67 g/kg) and one control group fed with a conventional basal diet. The corresponding feed was given for 28 days with free access to water. Body weight， food utilization rate， blood routine， blood biochemistry， urine parameters， organ coefficients and histopathological examination of the major organs were observed after anesthesia and dissection. RESULTS：The experimental rats had normal body weight growth and no obvious toxic reactions were observed. There was no statistical difference in hematological， biochemical， urine parameters and organ coefficients between the experimental and the control groups (P>0.05). No abnormality was found in gross observation during animal dissection. Some experimental groups showed statistically significant differences (P<0.05) in heart and kidney weight compared with the control group. Histopathological examination revealed no typical pathological histological changes or specific damage caused by the dietary supplement containing Cyclocarya paliurus and Fagopyrum tataricum. CONCLUSION：Under the conditions of this experiment，the dietary supplement containing Cyclocarya paliurus and Fagopyrum tataricum did not induce obvious toxicity in rats after oral exposure for 28 days.

Key words: Cyclocarya paliurus, Fagopyrum tataricum, subacute toxicity, Wistar rat, dietary supplement