Allozyme variability at eight loci among nine species belonging to the Stigmella betulicola, S. lapponica and S. marginicolella species-groups was studied using horizontal starch gel electrophoresis. Mean observed heterozygosity ranged from 0.086 in S. sakhalinella to 0.135 in S. continuella. Genetic distances were generally very large and ranged from 1.269 between S. confusella and S'. lapponica to 8.041 between S. sakhalinella and S. luteella. Moreover, S. continuella did not share any allele with S. alnetella, S. luteella and S. microtheriella. The species-groups could be clearly identified using their allozyme variability and for each species several diagnostic loci were assigned. A dendrogram based on Nei's unbiased genetic distances corroborated the current taxonomic views based on morphological characters.