Six plant powders including Cinnamomum zeylanicum (Lauraceae), Cuminum cyminum (Apiaceae), Curcuma longa (Zingiberaceae), Hyphaene thebaica (Arecaceae), Lawsonia inermis (Lythraceae) and Zingiber officinale (Zingiberaceae) were tested against Callosobruchus maculatus adults at four treatment levels of 20, 40, 60 and 80 gm of plant powders per Kg of cowpea seeds. Lethal concentration was determined at 24, 48 and 72 h after treatment, and lethal time was determined at 80 gm/Kg^-1 concentration. The results showed that, all botanical powders had effect on C. maculates and L. inermis was the most toxic, and the least toxic powder was C. zeylanicum. Furthermore, plant powder L. inermis at 80 gm/Kg^-1 achieved a lowest LT₅₀ value. The tested botanical powders represent valuable tools with potential of integration into the management of C. maculates adults.