The oleander aphid, Aphis nerii Boyer de Fonscolombe, is one of the common pests of ornamental plants in the families of Apocynaceae and Sclepiadaceae and distributed throughout the world, which has been responsible for the mortality of a large number of oleander (Nerium oleander L.) shrubs each year. In this research, the insecticidal activity of Ag nanoparticles against the A. nerii was investigated. Nanoparticles of Ag and Ag-Zn were synthesized through a solvothermal method, and using them, insecticidal solutions of different concentrations were prepared and tested on A. nerii. For comparison purposes, imidacloprid was also used as a conventional insecticide. In the experiments, the LC50 value for imidacloprid, Ag and Ag-Zn nanoparticles were calculated to be 0.13 μL mL-1, 424.67 mg mL-1, and 539.46 mg mL-1, respectively. The result showed that Ag nanoparticles can be used as a valuable tool in pest management programs of A. nerii. Additionally, the study showed that imidacloprid at 1 μL mL-1 and nanoparticles at 700 mg mL-1 had the highest insect mortality effect.