Nanoparticles can be synthesized by conventional methods (chemical and physical), but these methods have some drawbacks like use of toxic chemicals, required high temperature and pressure, and high cost. Because of this reason, green method has been gaining interest due to its ecological behavior like cost-effective, eco-friendly, and less time consuming. In the current ex-amination, Zinc oxide nanoparticles have been synthesized by Grewia asiatica extract which has never been used before at optimum conditions like Temperature, Concentration, and pH. Several microscopic and spectroscopic techniques were utilized to characterize the synthesized nano-particles such as, Scanning Electron Microscope (SEM), Uv-visible Spectroscopy (Uv-vis), Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-ray Spectroscopy (EDX). The syn-thesized nanoparticles were spherical in shape and had size in the range of 28-42 nm. The degradation of methylene blue via photocatalyst was investigated with the kinetic rate of the degradation process. The methylene blue was degraded by about 92% in 70 min with a rate constant of 0.0141 min-1. The work presented a novel ecological approach toward green syn-thesis of nanoparticles and the synthesized zinc oxide nanoparticles utilized as toxic dye removal catalysts which are ecological, cheapest, and easy to make.