Nanotechnology is one of the leading scientific fields since it combines knowledge from Physics, Chemistry, Biology, Medicine, Informatics and Engineering. In the present study, zinc oxide nanoparticles are synthesized using Justicia Adhatoda leaf extract as reducing as well as capping agent. The synthesized nanoparticles are characterized by various techniques such as XRD, FT-IR, SEM, and EDAX. The X-ray diffraction (XRD) analysis reveals the crystalline size of the synthesized nanoparticles. The presence of functional groups present in the sample was investigated through Fourier Transform Infrared Spectroscopy (FTIR). The surface morphological structure of ZnO nanoparticles was obtained using Scanning Electron Microscope (SEM). The Energy Dispersive X-ray Analysis (EDAX) was used to investigate the elemental composition of the sample. The synthesized nanoparticles will be useful for various applications in medicine and biology.