The composition of Chromaleana odorata and Aspilla africana leaf oil against cowpea seed storage bruchid, Callosobruchus maculatus F. was evaluated in the laboratory under the ambient temperature of 28+20C and 70+5% relative humidity. The bioactivity of the vital oil removed by hydro distillation from Chromaleana odorata and Aspilla africana leaves was evaluated as well as 12: 12h light: dark regimes for its biological activity. Specific components of the important oil were recognized through GC, GC-MS as well as GC-Co injection with accurate standards. A total of 17 and 30 basic compounds identity of the vital oil of the two plants were established as well as their relative proportion determined. 6 – phenylhexanoic acid had highest percentage composition in Chromaleana odorata essential oil (24.53%), while 3 – Hydroxy-alpha-ionene is highest in Aspilia Africana oil (21.68). The main components were found to be basically responsible for the toxic action of its vital oil against bruchids. The uppermost dosage of the vital oil of the plant materials tested evoked the highest mortality after 7 days post treatment. The two botanicals were expressively effective at the bioactive concentration of 0.25ml invoked weevil bruchid mortality in treated cowpea seeds. The adult bruchid mortality improved slowly with botanical concentration as well as with the exposure time. There is need to expand the use of botanicals particularly in the agricultural management pest sector.