Substrates of ytrria stabilized zirconia electrolyte were prepared by the ceramic injection molding, and then composite electrode slurry was made of platinum powder and yttria stabilized zirconia powder by ball milling, and then was brushed on both surfaces of the zirconia substrate. After this, the Pt/YSZ composites were sintered on the YSZ substrate under various temperatures. The microstructure of the surface and interface of the electrodes was characterized by scanning electronic microscope, and the results showed that the sintering temperature of the electrode has a remarkable effect on the microstructure of the composite electrode, and that the electrode and substrate was interconnected and interpenetrated. The electrochemical properties of the as-prepared electrodes were investigated by electrochemical impedance spectroscopy (EIS). The EIS experimental results reveal that the Pt/YSZ composite electrodes show the favorable electrochemical catalysis performance compared with the Pt electrodes.