The aim of this study was to evaluate the effects of three essential oils extracted from Matricaria chamomilla flowers, Pimpinella anisum seeds and Cuminum cyminum seeds as biopesticide against Sitophilus oryzae (L.)and Tribolium castaneum (Herbst). Wherefore, the tested oils were obtained by steam distillation and evaporation of the selected plant parts and then treated at concentrations of 25000 and 50000 ppm.The weights of grains and insects were estimated before experiments taken place. After application, the mortality rates of insects, weight of grains and weight of a live insects were determined after four days. Concerning; toxic effects assay, LC₅₀ of the oil of P. anisum (LC₅₀ = 21534.82ppm) was the most potent toxicant, followed by C. cyminum (LC₅₀ = 108310.64 ppm), and M .chamomilla (LC₅₀ =148175.77 ppm) in case of S. oryzae.Also, in case of T. castaneum, the oil of P. anisum (LC₅₀ = 24079.99 ppm) was the most potent toxicant, followed by C. cyminum (LC₅₀ = 29980.19 ppm), and M .chamomilla (LC₅₀ = 55621.91 ppm).In nutritional indices assay, all the tested oils had negative effects on feeding activity of S.oryzae and T. castaneum, particularly with the highest concentration (50000 ppm) of all tested oils. Ultimately, the three tested oils showed effects (toxic and antifeedant) against both insect species. This study may suggest using of such essential oils as potential biopesticides to protect stored grains from infestation by the examined insects.