Samples of adult, larvae and pupa of Ips subelongatus, and the blue-stained tissue and phloem of Larix olgensis bearing pupa cells, egg and larval galleries were collected. The fungi in the inside and outside of the insect body and gallery of larch log were cultured and isolated by Martin and PDA media, and the detection frequency of the fungi were counted. A total of 24 fungal species were isolated and identified, of which 7 species belong to Ascomycota, 2 species Basidiomycota and 15 species anamorphic fungi. All these fungi can be isolated from the insect-bored gallery, 21 species from the body surface of the beetle, and 6 species from the inside of the body. Ceratocystis fujiensis was the most frequently isolated fungus.