Micro arc oxidation (MAO) is comparatively new way of surface modification and strengthening of metal materials mainly. Beginning of this method can be seen from traditional anodizing and this is electrochemical process. Using micro arc oxidation allows obtaining polyfunctional ceramic materials with unique qualities: wear resistance, corrosion strengths, electric insulation and decorative overlays. Experiments were conducted on the equipment constructed in such way possible to make arc oxidation on surfaces with different overlay made by ion plasma method with thickness 5 micrometers and more. Technology of micro arc oxidation is used to process various metals and alloys (Al, Mg, Ti, Ta, Nb, Zr, Be, etc.). It is used for metals which oxide membrance is formed in electro chemical way and have monopolar d.c. link in the system metal – oxide – electrolyte. Micro arc oxidation is promising process which depends on various circumstances and regularities. Defining interconnection between treated material, parameters and conditions of process will improve exploitation qualities of overlays and will enlarge spheres of application.