This research work aims to prepare and characterize the effect of Al-doped ZnO nanoparticles (NPS) from the point of view of different physical properties for different applications. The co-precipitation method was used for preparing the desired samples, where ZnO was replaced by AlCl3. Then obtained samples were characterized by XRD to identify their structural phases. All samples exhibit a single-phase hexagonal wurtzite structure confirmed the substitution of Al on Zn sites. The average crystallite size was found to increase for all Al-doped ZnO samples. FTIR measurements were studied for Phonon modes. UV-vis spectra showed an absorption peak centered at 3.34 eV which represents the optical bandgap of ZnO. Al-Impurities acted to increase the value of optical transmittance, especially in the visible light region. The value of the calculated nonlinear refractive index is considered promising for different optoelectronic applications. In addition, the electrical conductivity of Al-doped ZnO samples increased at high frequency compared with that of pure ZnO due to the increase of available charge carriers after the replacement of Zn ions by Al ions. Also, dielectric constant and loss (tan ẟ) was found to be frequency dependent.