Atmospheric plasma sprayed alumina-titania (Al2O3-13% TiO2), coated on stainless steel (XC18), were characterized. The coating structure and morphology were studied by scanning electron microscopy. Their presented micro cracks, laminar splats. The coatings were studied by X-ray diffraction. The main phase transformation is that of alpha-Al2O3 into metastable gamma-Al2O3. The alpha-Al2O3 phase is due to the occurrence of partially melted particles Electrochemical behaviours of coatings were mainly investigated by potentiodynamic polarization and electrochemical impedance spectroscopy in 0.01 M [K3Fe(CN)(6)/K4Fe(CN)(6)] as a function of process parameters. Also, schematic equivalent circuit was proposed. The results were expected to facilitate the understanding and improvement of the coating behaviours.