Abstract: Background and Objective: Nowadays, chemical pesticides applied to control the field pests have deleterious effects on the ecosystem. Hence, there is an urgent need to find alternative pesticides to synthetic pesticides towards the control of selected 2 lepidopteran pests. To study the bioefficacy of the novel nonadecanoic acid isolated from the ethyl acetate extract of S. pseudocapsicum L. Materials and Methods: Using Thin Layer Chromatography (TLC), column chromatography, High Performance Liquid Chromatography (HPLC), Ultraviolet (UV), Fourier Transform-Infrared spectroscopy (FT-IR), Nuclear Magnetic Resonance (NMR) (1H, 13C), Gas Chromatography-Mass Spectrometry (GC-MS) the above said phytocompound was isolated and evaluated for its antifeedant, larvicidal and ovicidal activities against Helicoverpa armigera and Spodoptera litura at different concentrations of 250, 500, 750 and 1000 ppm. Results: The compound showed significant antifeedant, larvicidal and ovicidal activities against H. armigera and S. litura. Remarkably, the antifeedancy (86.30 and 81.10%), larvicidal (83.20 and 80.20%), ovicidal (81.70 and 80.10%) activities observed in the novel nonadecanoic acid at 1000 ppm concentration. Conclusion: The activities were concentration dependent for both the insects. Novel nonadecanoic acid compound well is used as an agent to prepare botanical new pesticidal formulations.