Advancement of biological process of nanoparticle synthesis is evolving into a key area of nanotechnology. Green synthesis of silver nanoparticles has been achieved using environmentally acceptable plant extract. The present research focuses on a rapid and eco-friendly method for green synthesis of silver nanoparticles from aqueous solution of silver nitrate using Carica papaya leaf extract as an effective reducing agent. The optical property of biosynthesized AgNPs were characterized using UV-vis Spectroscopy. The UV-vis spectra gave surface plasmon resonance for synthesized silver nanoparticles at 425 nm. X-ray diffraction (XRD) study revealed that most of the nanoparticles were face centered spherical in shape and grains are crystalline in nature. Phytosynthesized AgNPs using of Carica papaya leaf extract exhibited strong antioxidant activity that was confirmed by five different antioxidant free radical scavenging assays viz., DPPH, ABT+S, Superoxide, Hydroxyl and Nitric acid scavenging assays.