Abstract: A new environment-friendly electrolyte for anodizing of magnesium alloys were developed by orthogonal test．The corrosion current density（ I_corr） of the anodic film formed is0．1586μA／cm²．The pH value of electrolyte has great influence on the corrosion resistance of magnesium alloy．The component,structure and surface micrograph of the film were studied by EDAX, XRD and SEM．A few oxide complex was present in the film,although the main compound was MgO．SEM analysis showed that the film bonds to the substrate of magnesium alloy soundly．