Aqueous extracts of Securidacalongepedunculata and Artocarpusheterophyllus were screened for photochemicals and both were found to contain saponins, tannins, flavonoid, cardiac glycosides, anthraquinones and alkaloids. Biosynthesis of silver nanoparticles was carried out from these extracts. The formation and stability of the reduced nanoparticles in the colloidal solutions were monitored using UV-visible spectroscopy. The Fourier transform infra-red spectroscopy (FTIR), indicated the presence of bio-molecules responsible for reduction and stabilization of the nanoparticles. The morphology of the nanoparticles formed from Securidacalongepedunculata was flake like and that from Artocarpusheterophyllus was plate-like as shown by scanning electron microscopy (SEM). The nanoparticles from both plants showed potent anti-bacterial activities towards Staphylococcus aureus, a gram positive bacterium.