The 98 and 116 isolates of Pyricularia oryzae collected from Gyeong-nam Province in 1982 and 1983 were differentiated by using Korean differential rice cultivars. Twelve races from98 isolates and 11 races from 116 isolates of P. oryzae were classified indicating that KJ races group was and KI group was in total. The races KJ301 and KJ 401 were ca. in frequency among races identified.