Silvernanoparticles(AgNPs)wasachievedbyusingleafextractofBoragoofficinalisplantaseco-friendlyreducingandcapping agent. The results obtained from ultraviolet-visible spectrophotometer, dynamic light scattering, scanning & transmission electron microscopy, energy dispersive X-ray, and fourier transformed infrared confirmed the biosynthesis and the physical characterization of the produced nanoparticles. The synthesized Ag NPs was greatly more toxic to Spodoptera littoralis compared to crude extract. The LC50values of the crude extract, and synthesized Ag NPs were 22.6 and 0.33mg/g while LC90 values were 969.0 and 1.7 mg/g, respectively. Ag NPs and plant extract caused a significant elongation in larval period (18.02 and 18.82 days), respectively) compared with (15.78 days) in the control treatment. Whereas, there was no significant elongation in the pupal period in both males and females in case of Ag NPs and plant extract compared to the control treatment. Our results declared that the leaf crude extracts of B. officinalis and green synthesis of silver nanoparticles using it have the potential to be used as an ideal eco-friendly approach for controlling S. littoralis. This is the first report on the pesticide activity of this plant extract and its synthesized silver nanoparticles to control this insect pest.