In order to evaluate the diversity of morphological characteristics and to provide a criterion for choosing example varieties in rice DUS testing. Diversity analysis, including observed number of alleles, effective number of alleles and Shannon's information index, were conducted with 49 rice varieties which listed as example varieties in the DUS testing guidelines as material, combining with the 59 morphological characteristics investigated at Hanzhou in 2008. The clustering analysis for the example varieties was also conducted according to their species diversity parameters. The results showed that total of 201 and 262 alleles for 59 morphological characteristics were observed in the indica and japonica rice group, respectively, with an average of 3.4068 and 4.4407 alleles for each characteristic in the two subspecies. The Shannon's diversity index averaged from 59 morphological characteristics were 0.8318 with a range of 0~1.7674 and 0.9828 with a range of 0~1.8547 in the indica and japonica rice group, respectively. Several groups, with each includes 2-3 rice varieties with similarity over 0.7, were found in both indica and japonica rice group, based on the clustering results. The results indicated that the 49 example varieties, which with rich diversity in morphological characteristics, could be used for demonstration and adjusting for characteristics' describing in DUS testing. The 49 rice example varieties could be reduced to 43 according the threshold with similarity of 0.7. The result could provide a criterion for selection and optimization of example varieties in rice DUS testing system and could also give a reference for developing DUS testing guidelines for other plant species.