Two hundred twenty-six japonica rice varieties bred in Yunnan Province, China were inoculated at the seeding stage by spraying a spore suspension with one each of the six isolates belonging to the different Japanese races of blast fungus, Pyricuralia oryzae Cavara, collected in the Province, i.e. the race 001, 003, 007, 017t+, 037t+ and 137t+. The varieties tested were divided into seven groups, designated as I through VII, on the basis of the reaction patterns to the isolates. Varieties in the Group I, IV and II, III were further divided into three and two subgroups, respectively. One hundred ninety-eight varieties classified in the Groups I through VI were susceptible at least to one of the six isolates, and 28 varieties in the Group VII were resistant to all the isolate inoculated. The varieties in the Group VII were further divided into four subgroups by eight isolates which were virulent to the varieties bearing at least one of the following resistance genes, i.e. Pi-b, Pi-z, Pi-ta2 and Pi-zt. These isolates had been collected in Yunnan Province, Hainan Island of China and Japan. It is presumed that the Group I-1 corresponds to Shin 2 type according to the Kiyosawa’s classification, and that the varieties in the Group I-2 and I-3 have at least a resistance gene or genes to be identified yet. The varieties in the Group II may possibly have at least a resistance gene Pi-a, the Group III Pi-i, the Group IV Pi-k, the Group V Pi-km, and the Group VI Pi-ta, respectively. The varieties in the Group VII-1 may have Pi-b, the Group VII-2 Pi-b and other resistance gene or genes, the Group VII-3 Pi-zt, respectively. Seven varieties in the Group VII-4 which were resistant to all the isolates may have a resistance gene, or genes, which requires further identification.