Magnesium and its alloys are widely used in many industrial applications because of their high specific strength (strength/density) ratio. However, these applications are still restricted by the relatively poor surface resistance of these materials. To overcome the inherent drawbacks a useful solution is to deposit a protective coating on the magnesium alloys. The sol-gel process is an effective method for fabricating oxide films on a magnesium alloy in order to produce a higher corrosion resistance. The objective of this study is to comparatively investigate the process and properties of repeated sol gel oxide (ZrO2, Al2O3) coatings. The coatings were characterized by SEM, XRD, ellipsometry and the effects of the process on their properties were comparatively analysed.