A vanadium metal thin film is prepared by using magnetron sputtering at room temperature. Then, the film is annealed in a suitable oxide atmosphere. Finally, a high quality vanadium dioxide thin film with phase transition is prepared on an amorphous glass substrate. The X-Ray Diffraction (XRD) test result shows that the main component of the prepared film is vanadium dioxide. The Scanning Electron Microscope (SEM) test result shows that the prepared film is well crystallized and distributed. The film has its infrared transmittance of 67% at 2400 nm wavelength at room temperature and has its infrared transmittance of 9% at the same wavelength at room temperature. The transmittance difference is 58%. Therefore, it has a good infrared transmittance adjustment ability. In addition, the difference between the optical transition and the electric transition of the film is analyzed. It is found that its electric transition temperature is 4.7℃ higher than its optical transition temperature. This method is suitable to prepare large area vanadium dioxide films and is of significance to the research and application of smart windows.