ZnO nanostructures were prepared from zinc sulfate and zinc nitrate precursors by ultrasonic spray pyrolysis (USP) method in air atmosphere condition at 800 degrees C reaction temperature. Effects of the precursor's properties on the morphology, size and chemical features of the products were investigated. Energy dispersive spectroscopy (EDS) was performed to determine the chemical composition of prepared structures. Though, directly producing of the ZnO nanostructures using zinc nitrate precursor by USP method was possible, it was understood that extra heat treatment was necessary to obtain ZnO structures when zinc sulphate precursor was used. The size, shape, and surface morphology of samples were characterized by scanning electron microscope (SEM) revealed that agglomerated 30-50 nm sized nanoparticles were obtained from zinc nitrate precursor. Also, flat like shaped ZnO nanostructures were formed by using zinc sulfate precursor.