Here, we have used the green method for synthesis of silver and gold nanoparticles. In the present study the silver (Ag) and gold (Au) nanoparticles (NPs) were synthesized by using the aqueous bark extract of Indian spice dalchini (Cinnamomum zeylanicum) (C. zyelanicumorC. verumJ. Presl). Additionally, we have used these synthesized nanoparticles for mosquito control. The larvicidal activity has been tested against the malaria vectorAnopheles stephensiand filariasis vectorCulex quinquefasciatus. The results were obtained using UV-visible spectrophotometer and the images were recorded with a transmission electron microscope (TEM). The efficacy tests were then performed at different concentrations and varying numbers of hours by probit analysis. The synthesized AgNPs were in spherical shape and average sizes (11.77 nm AgNPs and 46.48 nm AuNPs). The larvae ofAn. stephensiwere found highly susceptible to the synthesized AgNPs and AuNPs than theCx. quinquefasciatus. These results suggest that theC. zeylanicumsynthesized silver and gold nanoparticles have the potential to be used as an ideal ecofriendly approach for the control of mosquito.