The orchid symbiotic fungi were isolated from the roots of Korean native orchid (Cymbidium goeringii) collected and Chinese orchid (C. sinense) obtained from greenhouses. They were identified as a species of Rhizoctonia, based on the sequences of 18r rDNA, the microscopic observations of mycelia, and the symbiotic relationships with commercial orchids. The isolate collected from Chinese orchids was revealed to be a species of Ceratobasidium endophytica, and to be different from the other isolates at the thickness of the mycelia stained in the root cells of Korean native orchids. The other isolates collected from the Korean native orchids were considered to be a species of Tulsanella repens (anamorphic: Epulorhiza repens) or its related one. The physiologic or microscopic variations were oftenly observed among them, but the tendency of grouping these in the 18s rDNA sequences were observed to be consistent with those of the localities collected. The further taxonomical segregating for Korean symbiotic fungi was not made because the information concerned were limited in this moment, but was recognized as based on the sequences of 18s DNA.