In the present work, we have synthesized ZnO nanostructures by sol-gel method in air at different selected sintering temperatures ranging from room temperature to 400 0 C and studied their structural, optical and ferroelectric properties. The synthesized samples are characterized by X-ray diffractrometer for structural properties and the optical properties are measured through UV-Visible spectrophotometer and Photoluminescence. The X-ray diffraction pattern indicates the pure phase formation of ZnO. Furthermore, photoluminescence spectra also confirm the formation of wurtzite structure of ZnO. X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) studies show that the particle size of ZnO nanostructures increases with increasing the sintering temperature. The optical band gaps calculated through UV spectroscopy are found to be decreasing from 4.47 to 3.73 eV for samples sintered at room temperature to 400 0 C, respectively. Moreover, a weak ferroelectricity has been observed in ZnO nanostructures at room temperature through Polarization vs Electric field (P-E) loops.