This study was carried out to obtain basic data on mycelial growth characteristics for an artificial cultivation of Grifola frondosa. Ten strains of G. frondosa were collected from Korea, China and Japan and investigated its optimal culture condition. Among four kinds of mushroom culture media, PDA medium was selected as the suitable culture medium. The optimal conditions for the mycelial growth of G. frondosa in PDA medium were 25 oC and 4~5 of pH, respectively. The carbon and nitrogen sources for the optimum mycelial growth were fructose and peptone, respectively, and the highest mycelial growth was observed when the C/N ratio was 10~20.