Considerable differences in flavonoid composition of the trunkwood characterize different specimens of Myroxylon balsamum (L.) Harms. Only calycosin among the 11 flavonoids found in M. peruiferum L.f., presently considered synonymous with M. balsamum, had previously been located in the latter species. Two of these flavonoids, 2'-hydroxy-7,3',4'-trimethoxyisoflavanone and 2'-hydroxy-7,3',4'-trimethoxyisoflavone are new natural products.