Starch gel electrophoresis was used to compare eight loci in six enzymatic systems of 17 samples of the groundnut seed-beetle, Caryedon serratus (Ol.) (Coleoptera: Bruchidae) bred on five different host-plant species: Arachis hypogaea, Bauhinia rufescens, Cassia sieberiana, Piliostigma reticulatum and Tamarindus indica. The rate of polymorphism was 44.8%. The average genetic diversity (Hw) was 0.184. Allozyme variability analysis indicated that seed-beetles associated with P. reticulatum and groundnut, Arachis hypogaea were genetically similar, whereas other samples clustered according to their host plant species. Geographical distances less than 400 km were not decisive for the genetic structuring of samples associated with a given host plant.