The effect of microstructure and substrate on the electrical conductivity of yttria stabilized zirconia film (YSZ), prepared by metal-organic chemical vapor deposition (MOCVD), was investigated by complex impedance analysis. The electrical conductivity of the thin films with columnar structure was controlled by the oxygen ion conduction across the columnar grain boundary. The YSZ thin film deposited on Al2O3 (1 0 2) MgO (1 0 0) and SiO2 with columnar grains exhibit the electrical response of polycrystalline ceramic specimen. The dependence of activation energy and impedance diagram on substrate is increased according to the mismatch of thermal expansion coefficient between film and substrate.