Abstract: Micro-arc oxidation films were prepared on the surface of SiC_p/Al composite using NaAlO₂ and NaOH as electrolyte systems in constant voltage. The microstructure and phase composition of the films were characterized by scanning electron microscope（SEM） and X-ray diffraction（XRD）. The bonding force of films were analyzed by scratch tester. The corrosion resistance was characterized by electrochemical workstation. The results indicate that the micro-arc oxidation process of SiC_p/Al composite includes three stages under the constant voltage mode: passivation and micro-arc discharge,uniform spark and arc discharge. With the increase of positive voltage, the micro-arc oxidation film gradually becomes continuous, and the film thickness increases first and then decreases. When the positive voltage is high, the film is prone to microcracks. Positive voltage has a certain effect on the phase of micro-arc oxidation films on SiC_p/Al composite. The maximum bonding force between micro-arc oxidation film and substrate is 23.55 N at 450 V. The corrosion resistance of SiC_p/Al composite can be improved by micro-arc oxidation at different positive voltages. The corrosion resistance of the micro-arc oxidation film is excellent when the positive voltage is 550 V.