Diversity of endophytic fungi of two species associated with host plants, Pinus densiflora and Larix kaempferi in Mt. Oser were investigated. Endophytic fungi were isolated from surface sterilized leaves of the 13 host plants and identified by morphological traits and rDNA ITS sequences analysis. Totally 37 isolates were discovered and identified into 17 taxa. Of them, 59% isolates belonged to Leotiomycetes, 30% isolates Sordariomyetes, 8% isolates Dothideomycetes and 3% isolates Agaricomycetes. Results showed a similar diversity pattern with previous studies. Also, species diversity (H’) of endophytic fungi isolated from L. kaempferi was higher than that from P. densiflora. The endophytic species composition showed significant differences between host plants. Particularly, taxon of Lophodermium is a major genus in the host plants. However, critical research of the endophytic species diversities within the genus in Korea is required. The communities of endophytic fungi isolated in this study showed differences in diversities and species composition between host plants.