Nanotechnology has become promise field as a new approach for pest managing in recent years. Laboratory experiments were conducted to evaluate the toxicity of synthesized silver nanoparticles (AgNPs) by using aqueous plant extract (Rosmary, Laura and Cardamom) and their concentrations against main stored grain insect pest (Sitophilus granarius), microbial contents and nutritive value. Wheat grain which were treated with Rosmary 5 showed 100% mortality for adults of S. granarius after 120 h., while the same efficacy of Laura5 and Cardamom 5 recorded after 144 h. LC₅₀ and LC₉₀ values of the synthesized silver nanoparticles were identified against S. granarius indicated that the toxicity of AgNPs varied according to the plant extractio and exposure period.The carbohydrate, fiber, fat, protien and ash content of the treated wheat grains were significantly higher than control. While, the microbial contents were not detected after treatments by most AgNPs concentrations. In conclusion, the synthesis of AgNPs with high amounts from each plant extract and lower concentration from AgNo3 (1 µg/ml) can be used as a valuable tool in pest management programs of S. granarius, reducing  microbial content, and increasing the nutrition values, that led to increase shelf life of stored wheat grain. The results showed that these compounds could be used as a source of bioactive compounds safely for ecosystem.