To find the alternate ones with insecticides of synthesis, the extracts of plants are more and more used by the peasants to protect stocks from harvest against the devastating insects. Small fireclay cups phytochimic and insecticidal are made on three plants (Crataeva religiosa, Ficus thonningii and Tapinanthus bangwensis). The identification of the active ingredients present in the three plants show that they contain polyphenols, flavonoides, alkaloids, tannins, saponosides, etc. The insecticidal tests showed that the extract with the chloroform (HEY) of Crataeva religiosa is effective on Callosobruchus maculatus and Sitophilus zeamais while extracts with cyclohexan (EC) and methanolic (EM) are effective only on Callosobruchus maculatus. It sucked shown that the extract with chloroform gives a better mortality rate and that Callosobruchus maculatus is more sensitive to the treatments the strong amount (50 mg/mL). For the study of emergences, the methanolic extract of the sheets of Crataeva religiosa ensures a better protection of the medium on Sitophilus zeamais. It was also shown that the extracts with the cyclohexane and methanolic of Ficus thonnigii are more effective on Callosobruchus maculatus. Thus, the methanolic extract (EM) of Ficus thonningii reduces considerably the number of insects emerged in the short run on Callosobruchus maculatus. The tests relating to Tapinanthus bangwensis showed that the extracts cyclohexanic, chloroformic and methanolic are effective on Sitophilus zeamais. The extracts with the cyclohexan and the methanol of Tapinanthus bangwensis reduce considerably the number of insects emerged on Sitophilus zeamais and long-term. Broadly Tapinanthus bangwensis is more effective on the two studied insects and Callosobruchus maculatus is the species most sensitive to the treatments. It is thus the most promising plant.