This study was conducted to investigate genetic characteristics of 25 Pleurotus eringii strains that have been released in Korea based on cultural, morphological features and PCR fingerprints. Strains PER-007 and PER-012 showed distinct cultural characteristics in growth rate, morphological characteristics of mycelial colony and fruiting bodies when compared to those of other strains. Strain PER-007 did not form primordium initiation in sawdust medium and PER-012 also showed different phenotypes on fruiting bodies . Eleven URP primers were used to detect PCR polymophic bands in P. eringii strains. Primers URP1F, URP2R, URP2F, URP4R, URP6R, URP9F and URP17R were selected as useful primers for amplifying PCR polymorphic bands in P. eringii strains. The genetic similarity index was calculated by using PCR polymorphic bands amplified by eight URP primers among the 25 strains. The P. eringii strains were grouped by four distinct clusters on the UPGMA analysis. The genetic similarity values ranged from 100% to 76% were observed in three major groups, suggesting close genetic relatedness of them. Exceptionally, PER-007 and PER-017 were involved in outgroup.