Abstract:Sb-doped SnO_2/SiO_2 nano-composition thin films were prepared by sol-gel method.The crystal structure and surface topograph of the thin films were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR) and atomic force microscopy(AFM).The optical properties of the thin films were studied by UV-VIS spectra.The gas-sensing property was tested by p-polarized reflectance.The experimental results show that,the crystalline grain size is about 34 nm,the specific surface area is large,and the duty porosity is high;the optical transmissivity is higher,near 95 % in visible spectrum range.Further,the gas sensitivity of Sb:SnO_2/SiO_2 nano-composition thin films is higher than one of Sb:SnO_2 thin films.