Abstract: The development of micro -arc oxidation and principles of ceramic coating preparation and growth regularity on magnesium were reviewed in this paper. The influences of voltage, electric density, electrolyte systems on the performance of ceramic coating were analyzed. The paper also briefly introduces the influences of electrolyte conductance rate and chemical in electrobath on oxidation membrane. Research deficiencies and development direction on micro-arc oxidation surface treatment on magnesium alloy were put forward.