Abstract: The esterase isozymes of twenty-nine accessions of cultivated and wild buckwheat belonging to eight species of genus Fagopyrum were studied by means of polyacrylamide gel eletrophoresis(PAGE).The results showed that there are a total of thirty-one bands of esterase isozymes,with a range from four bands to nine bands among different buckwheat species.F.esculentum and F.tataricum respectively have a total of eight bands and nine bands among different accessions.The results of the zymograph analysis and the clustering showed that there are much great difference of zymographs between the big-achene group and the small-achene group and that F.megaspartanium and F.pilus are close in clustering tree to F.esculentum and F.tataricum,respectively,supporting Chen’s hypothesis that F.megaspartanium and F.pilus may be the ancestors of F.esculentum and F.tataricum,respectively.