Recent studies have shown that Leptographium lundbergii and L. truncatum are morphologically similar. This has led to suggestions that the species, which both occur in Europe and are associated with European scolytid bark beetles, might represent a single taxon. Synonymising these two species based on their similar morphology has been resisted in the past. This is primarily due to the fact that L. lundbergii is the type species of the genus and it was felt that such a decision should be based on more intensive study. PCR amplified DNA fragments of isolates of L. lundbergii and L. truncatum from numerous geographic origins were compared on the basis of the DNA sequence from the ITS2 region and part of the 5.8S gene of the rRNA operon. Phylogenetic analyses show that L. lundbergii and L. truncatum isolates group together and separate from the outgroups, L. wingfieldii, Ceratocystis fimbriata and C. albofundus. Based on these data and the morphological similarity of the two species, we conclude that L. truncatum is a synonym of L. lundbergii.