Sb-doped SnO2thin films at different thickness have been grown by sol-gel dip-coating method. All of the films exhibit degenerate semiconductor behavior and high free carrier concentrations. In the films, electrical transport can be explained reasonably well by assuming the electron-electron interactions (EEIs) contribution to the measuredelectrical conductivity. Our experimental observations are consistent with the theoretical description of the EEI. The effect of films thickness on the EEI contribution is also discussed. When the thickness of film reaches to 1550 nm, the agreement between the EEI theory and experimental data becomes unsatisfactory.