Abstract:The taxa of theAphis fabaegroups.str.are morphologically difficult to separate or inseparable. Vertical starch gel electrophoresis of members of theAphis fabaecomplexs.str. ands.l.was carried out to find specific isozymic characters. Analysis of the banding patterns of 17 genetic loci reveals that each of the 18 taxa investigated can be clearly identified. A biochemical key is presented.