Metal V films were prepared on quartz substrates via magnetron sputtering, and then converted to VO₂ films via vacuum annealing. The effect of annealing temperature on the surface morphologies, crystalline structures, optical properties and electric properties of VO₂ films was investigated. The results show that the crystallinity of the films increases with the increase of annealing temperature from 300℃ to 450℃. The films annealed at 400℃ and 450℃ are a pure monoclinic phase. The grains grow better and the grain boundaries are clear. The valent states of V element for different samples include +4 and +5 states. The presence of V⁵⁺ in the films is due to the oxidation in atmosphere. The annealing temperature has little effect on the visible transmittance, but the solar modulation efficiency increases. The metal-insulator transition (MIT) temperature and the resistance of semiconductor phase increase with increasing the annealing temperature. The resistance change amplitude across the MIT for the films annealed at 400℃ and 450℃ is more than 2 orders of magnitude. The hysteresis width and the MIT temperature of the film annealed at 450℃ are 14.6℃ and 61.0℃, respectively.