cDNA clones coding for three different binding proteins were isolated from an antennal library of Heliothis virescens. The deduced amino acid sequences showed only moderate homology to each other but shared several common structural features. Based on a comparison with the predicted primary structures of antennal binding proteins from different moth species, one of the clones (Hel-1) was found to encode a pheromone binding protein, whereas the two others (Hel-10 and -11) encode general odorant binding proteins.