The green synthesis method of nanoparticles using plant extracts attracts great attention as a reliable, low-cost, sustainable, environmentally friendly protocol that prevents or minimizes waste generation. In this study, Punica granatum peel extract was used as the reducing plant material and zinc acetate dihydrate (Zn (CH3COO)2. 2H2O) solution was used as the starting metal. In the synthesis, optimum conditions were determined by UV visible spectroscopy using different metal ion concentrations, plant extract amount, temperature, and pH parameters. For characterization of ZnONPs synthesized at optimum conditions, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), Dynamic Light Scattering (DLS), Zeta potential and Atomic Force Microscope (AFM) analyzes were made. It has been determined that the synthesized ZnONPs are spherical, have good stability, high purity, and nanoscale. The free radical scavenging capacity of biosynthesized ZnONPs was evaluated by DPPH analysis with different concentrations. The IC50 value was determined as 250µg ml-1.