The results of a study on the efficiency of the alkaloid and phenolic extract of the seeds and leaves of the sesban plant on the adults of the red flour beetle Tribolium castaneum showed a variation in the average mortality of the insect adults, as it reached 66.25% and 68.33% for the alkaloid and phenolic extracts, respectively. The results of the statistical analysis showed that there were no significant differences in the average mortality of both extracts. The results of the study indicated that the leaf extract showed a significant superiority in the average killing of adults of the red rusty flour beetle compared to the seed extract, reaching 70.00% and 64.58%, respectively. In addition, the effect of concentrations of 0.25%, 0.50%, 0.75%, and 1% showed a direct relationship in increasing the average mortality of adults with increasing concentrations, reaching 50.33%, 63.33%, 73.33%, and 81.67%, respectively.. The results were confirmed by LC50 values and relative toxicity, indicating that the alkaloid extract from sesban leaves showed the highest toxicity compared to the other extracts, with a lower LC50 value of 0.210% and a relative toxicity of 180.95.