The Ag/TiO₂ film was prepared on glass substrate by magnetron sputtering, and the effects of film layer thickness on transmittance and thermal insulation of Ag/TiO₂ films were studied. Results showed that the average transmittance of infrared light decreased from 42.06% to 7.70% and the temperature difference increased from 1.9 ℃ to 5.7 ℃ with the increase of Ag film’s thickness from 6.7 nm to 9.5 nm, while the average transmittance of visible light firstly increased and then decreased. The average transmittance of visible light was up to a maximum of 70.85% at the Ag film’s thickness of 7.7 nm. The average transmittance of infrared light increased from 34.12% to 38.28%, while the average transmittance of visible light and the temperature difference firstly increased and then decreased with the increase of TiO₂ film’s thickness from 4.1 nm to 16.7 nm. The average transmittance of visible light was up to a maximum of 70.85% at the TiO₂ film’s thickness of 10.4 nm, and the temperature difference was up to a maximum of 5.2 ℃ at the TiO₂ film’s thickness of 13.6 nm.