The preliminary phytochemical analysis of ferns viz., Cyclosorus interruptus (Willd.) H.Itô (Theylepteridaceae), Christella dentata (Willd.) (Forssk.) Brownsey et Jermy (Theylepteridaceae), and Nephrolepis cordifolia (L.) Presl revealed the presence of the secondary metabolites like alkaloids, steroids, tannins, flavonoids, terpenoids, cardiac glycosides, phenolic compounds and terpenoids in crude extract. The characteristic colour change and the UV- Vis spectrum obtained for the silver nanoparticles (AgNPs) formulation of the experimental ferns confirmed the synthesis of nanoparticles (433.50nm, 450.00nm and 444.00 nm for C. interruptus, C. dentata and N. cordifolia, respectively). The pesticidal property of the crude extracts and ferns-AgNP (Fe-AgNP) were evaluated in the laboratory on Spodoptera litura (Fab.)(Lepidoptera: Noctuidae) third instar larvae. The crude extract and Fe-AgNP formulations exerted their influence on the developmental period, pupation rate, pupal weight and adult emergence which were reduced significantly. They also caused larval, pupal and adult deformities that confirm the insecticidal activity of the plant.