In this work, tungsten oxide thin films were grown on preheated glass substrates by spray pyrolysis technique. The microstructure and electrical properties of the prepared samples were studied. The influence of post deposition thermal annealing on the crystallization of prepared films has been investigated. X-ray diffraction (XRD) confirmed that all samples prepared at different deposition temperatures, $T_{dep} \le 350^\circ$C, are almost in the amorphous form, while sample deposited at $T_{dep} = 400^\circ$C possess hexagonal structures with a preferential orientation along (200) direction. Moreover, the degree of crystallinity was improved by thermal annealing. The microstructural parameters (crystallite size and microstrain) were determined using Sherrer’s formula measurements of FWHM of the characterized peaks. The dark electrical resistivity at different deposition temperatures, $T_{dep}$ was measured at room temperature. The value of activation energy is calculated and is found to be ranged from 0.79-0.89 eV depending on the annealing temperature.