Electrophoretic examination of the hexaploid Rumex acetosella L. revealed a substantial amount of genetic variation. Both the genotype frequencies and the distribution of genotypes varied greatly between populations. The North American populations of ssp. angiocarpus possessed less genetic variation than did the European populations of ssp. acetosella or angiocarpus, which may be due to the history of the species. The European populations of ssp. acetosella and angiocarpus appeared to be genetically more similar than the angiocarpus populations from different continents. It is likely that these two subspecies do hybridize when their populations are sympatric. The results do not confirm the presence of an association between morphometric and allozyme variation in R. acetosella.