AbstractTo collect more information about the organisms causing sap-stain, a thorough survey was conducted in Koreas sawmills that process logs and boards of Japanese red pine and Korean pine. Sap-staining fungi were isolated and identified using morphological and molecular methods. The 482 isolates obtained were distributed into at least nine species of ophiostomatoid fungi. In both pine species, the frequency of ophiostomatoid isolates was much higher in boards than in logs. Three species, Ophiostoma koreanum,O. floccosum, andO. piliferum, were found on both logs and boards. TwoPesotumspecies from Japanese red pine were isolated only from logs. Our results show that the dominant species in both logs and boards wasO. koreanumfrom Korean pine. However,O. koreanum,O. floccosum, andO. ipswere the most frequently found species in this study.