Chaoteng grape, as a somatic mutant of Fujiminori, is quite difficult to be distinguished from its parental line by morphological or even RAPD methods. Here we provided an improved AFLP protocol suitable for grape whose leaves are highly rich in impurities including polysaccharides and polyphenols. And the two grape cultivars were successfully discriminated when AFLP primers M-CAT and E-ACG were applied,where Chaoteng produced a specific AFLP product of 167 bp in length.