Unpeeled pinelogs attacked by Blastophagus minor. B. piniperda and Ips acuminatus, and spruce logs attacked by I. typographus were examined for blue-stain fungi. Ophiostoma canum and Trichosporium tingens occurred in more than 50% of the wood attacked by B. minor. Other blue-stain fungi and molds were sporadically present, and yeasts occurred in most tests. The 2 fungi named were isolated from both larval and adult beetles but were absent generally from the galleries of B. piniperda. O. pini was often found here, but could have entered from the air. It may also be associated with I. acuminatus. 2 other Ophiostoma spp. were often found. O. penicillatum and numerous yeasts occurred regularly in galleries of I. typographus in spruce. Cladosporium herbarum and Pullularia pullulans were found in some galleries, but not frequently enough to warrant linking them with a particular beetle sp. These latter fungi are prevalent in the air and in tests taken from knots and wounds.