In recent years, the use of zinc oxide nanoparticles (ZnO NPs) has attracted considerable attention due to its unique properties. In this study, ZnO nanoparticles were synthesized by a simple and repeatable method with thermal decomposition of a zinc-based metal organic framework (Zn-MOF). MOF-5 was prepared by solution (at room temperature) and solvothermal (at 90 °C) methods in dimethylformamide (DMF) as a solvent via the self-assembly of zinc acetate and dehydrate benzene-1,4-dicarboxylate (BDC) as metal ion center and organic bridging ligand respectively without and with tri-ethylamine (TEA) as capping agent. The result products were characterized by Fourier transform infrared (FTIR) for investigation functional groups, X-ray diffraction (XRD) for determination of crystalline structure, scanning electron microscope (SEM) for evaluation of size and morphology, energy-dispersive X-ray spectroscopy (EDS) for determination of chemical composition, and diffuse reflection spectroscopy (DRS) for investigation of Ultraviolet (UV) protective properties. The antibacterial activities of ZnO NPs were studied against Escherichia coli ( E. coli).