SnO2/Ag/SnO2 trilayer thin films were prepared on glass substrates by RF magnetron sputtering of SnO2 with different O2/Ar ratio and DC magnetron sputtering of Ag. Several analytical tools such as Hall measurements, fourpoint probe and ultravioletvisiblenear infrared (UVVisNIR) spectrophotometer were used to explore the causes of the changes in electrical and optical properties. When O2/Ar ratio is 1∶14, the film had a figure of merit of 1.69×10－2 Ω－1, the resistivity is 9.8×10－5 Ω·cm, and the sheet resistance is 9.68Ω/sq, while the average transmittance is still as high as 85% in the visible light region. In addition, when O2/Ar ratio is 1: 14, The flexible SnO2/Ag/SnO2 trilayer thin films with excellent photoelectric performance can be obtained by magnetron sputtering on PET substrates, the average transmittance is above 85%, the resistivity is 1.22×10－4 Ω·cm, and the sheet resistance is 12.05 Ω/sq.