This Research was the standardization of nutrient sources by reviewing the possibility of cultivation and analysis of imported nutrient sources used in Pleurotus ostreatus culture. As a first result, the concentration of heavy metals was not detected or trace, and the total nitrogen content of cotton seed pomace was 6.22% in Australia, which was higher than that of Chinese or USA. As a second result of physical properties of nutrient sources, the water holding capacity of beet pulp from Egypt was higher with increasing pressure. The volume water content of US was highest at 400hpa and 500hpa in case of cottonseed meal. Third, the content of total nitrogen was the highest at pH 5.51 and the total nitrogen content was the highest at 2.45, and the C/N ratio was the highest at 28.18. Last result shows that first germination day, yield and biological effciency of all treatments were not significant differnet except T2. These results shows that australian cootton was inappropriate to Pleurotus ostreatus culture. Nevertheless, the safety and standardization of the Pleurotus ostreatus culture medium should be assured by reviewing the media low material importing season, mushroom yield and nutrient sources.