In 1991. bollworm moths were captured in pheromone traps in appreciably greater numbers than were tobacco budworm moths in central (Boone County), southwest (Barton and Greene Counties), south central (Wright County), and southeast (New Madrid, Stoddard, Scott, Dunklin, and Pemiscot Counties) Missouri. Bollworm moths whereas tobacco budworm moths were captured by the first week in may in the southern counties. Vial bioassays conducted on bollworm moths from Boone (n=10) and Wright (n=18) counties gave mean (±SD) LD(50)'s for cupermethrin of 1.00 (0.55) and 0.83 (0.21) µg/vial and only 4 moths (0.7%) survived 10.0 µg/vial. Piperonyl butoxide and amitraz synergized the toxicity of cypermethrin to bollworm moths. These field bioassays utilizing bollworm moths and cypermethrin indicated that bollworms in Missouri remain susceptible to pyrethroid insecticides.