In this paper, substrate effect on electrochromic properties of Nb2O5:TiO2 nanocomposite thin films have been investigated. Thin films have been deposited by thermionic vacuum arc deposition technology. Nb2O5 and TiO2 are known to be electrochromic materials. Nb/Ti rate was obtained 1.4. Average thicknesses of the films were found as 113 nm and 111 nm and band gap values for bleached states were calculated as 3.96 eV and 3.85 eV for the films deposited onto ITO and FTO coated glass substrates, respectively. The coloration efficiency values were calculated as 17 cm2/C and 26 cm2/C for the film onto ITO layered glass substrate and 31 cm2/C, 23 cm2/C and 24 cm2/C for the film onto FTO layered glass substrate at a different wavelength values in the visible region. The obtained results shows that films for each transparent conductive oxide material is promising material to obtain the high performance TiO2 active layer.