Cowpea chlorotic mottle virus was transmitted by the bean leaf beetle, Cerotoma trifurcata, and by the spotted cucumber beetle, Diabrotica undecimpunctata howardii. Three strains of the virus were transmitted at low levels. Levels of transmission were highest when virus was acquired from and transmitted to beans [Phaseolus vulgaris]. Levels were much lower when the virus was either acquired from or transmitted to cowpeas [Vigna unguiculata]. Lespedeza cuneata, which may be an overwintering host, was a poor source of virus for vectors.