Ceramide monohexosides from Aspergillus fumigatus 2140 and 2109 strains and Aspergillus versicolor 550 strain, obtained by silica gel 60, and Iatrobeads chromatography were analysed using high-resolution 1D-, 2D-1H-NMR and 13C-NMR spectroscopy and fast atom bombardment mass spectrometry (FAB-MS). The ceramide monohexoside fraction (CMH) from A. fumigatus 2140 and A. versicolor 550 was identified as glucosylceramide, whereas glucose and galactose were present at a ratio of 1:1 in the CMH of A. fumigatus 2109. The major glycosphingolipid has a particular ceramide composition consisting of 9-methyl-4,8-sphingadienine linked to a 2-hydroxyoctadec-3-enoic acid. Although the structures presently described are similar to those of monohexosylceramides from other fungi, including edible ones, this is the first report on their occurrence in species pathogenic in humans.