Pleurotus has increased rapidly production and consumption because of highly nutritional value, natural healthy foodand so on. The basic studies for Pleurotus need for development of mushroom industry. This study was to investigate the culturalcharacteristics among 15 strains of 6 species and to analyze their phylogenetic relationships. The cultural characteristics wereinvestigated by mycelial growth activity at different media, temperature and pH. The optimum media for mycelial growth wereYM and MCM in most species. The optimum temperature for mycelial growth were 25^oC and 30^oC. The optimum pH formycelial growth were widly range from pH 5.1 to 7.4. Through the RFLP (restriction fragment length polymorphism) of IGS(intergenic spacer) I region in ribosomal DNA, it was analyzed phylogeny of interspecies and intraspecies. Each species wasdiscriminated well as isolates within each species formed clade to be distinguished other species. P. florida was highly similar to P.floridanus, and P. flabellatus was P. cornucopiae. P. fuscus var. ferulae was highly similar to P. eryngii but discriminated differentspecies in analysis of RFLP of IGS I region and showed different characteristics in mycelial culture. RFLP of IGS I region wasuseful of studying phylogenetic relationships of species and population.