The effectiveness of treatment with Petroselinum sativum oil for the protection of wheat grain and mung bean seeds Vigna radiata (L.) against the rice weevil S.oryzae and the cowpea weevil, C.maculatus was determined through laboratory tests by coating grains and seeds with P.sativum oil at LC25, LC50 and LC95 's levels. S.oryzae adults were more sensitive to the oil than C.maculatus adults at LC50 and LC95's level (2.3 and 3.5, 13.5 and 19.1 ml/kg for S.oryzae and C.maculatus). Oil treatment at three tested levels gave a severe reduction in egg deposition, hatchability and percentage of progeny, especially at LC95's level which was highly effective on the reproductive capacity of the two tested insects to the extent that no offspring was produced by the adults, and complete protection to wheat grains against S.oryzae and mung bean seeds against C.maculatus was achieved at this level (LC95's). Oil treatments seem to have adverse effect on treated wheat grains and mung bean seeds germination, but the percentages of water absorbed did not vary consistently with the different concentration of oil applied (after 1,5 and 24 hr.). Also, tested oil decreased the amount of total chlorophyll in case of wheat grains and mung bean seeds especially at LC95's level.