In this work, the gallium oxide (Ga2O3) thin films were deposited on silicon substrate using radio frequency (RF) magnetron sputtering and these Ga2O3 thin films were subjected to post-deposition annealing in oxygen ambient at different temperatures of 400, 600, 800, and 1000℃ for 60 minutes. The structural properties of post-deposition annealed Ga2O3 thin films were characterized using grazing incidence X-ray diffraction (GIXRD). Atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM) were employed to attain the three-dimensional surface topographies and morphologies, respectively, for the investigated Ga2O3 thin films. In additional, elemental composition of these thin films were characterized using energy-dispersive X-ray spectroscopy and thickness of the investigated Ga2O3 thin films were estimated based on the cross-sectional FESEM images. Current-voltage characteristics of the Ga2O3 thin films subjected to different postdepositional annealing temperatures were also presented in this work.