This study was conducted to investigate the diversity of culture-dependent fungal species in the sawdust media of Lentinula edodes. A total of 405 fungi were isolated from the specimens and identified to belong to 24 genera and 42 species. Among the identified 42 species of fungi, 26.2% belonged to Penicillium sp., 9.5% belonged to Trichoderma sp., and 64.3% belonged to others. Especially, Trichoderma harzianum, which is a causal agent of fungal disease in mushroom, was found on all the farms, and showed the highest frequency among the identified fungi. Community analysis showed that the fungal diversity patterns of the samples were similar to each farm and many kinds of fungi existed in the sawdust media at high levels. These results showed that the management of internal environments would be required for the stable cultivation of Lentinula edodes.