Micro-arc　oxidation　(MAO)　can　improve　corrosion　resistance　of　magnesium　alloys,　while　the　further　promotion　of　corrosion　resistance　is　significantly　restricted　due　to　the　existence　of　pore　and　micro　crack.　In　this　study,　three　types　of　LDH/MAO　coating　were　prepared　via　covering　layered　double　hydroxide　(LDH)　on　MAO　pre-treated　AZ31　alloy,　and　the　effects　of　these　three　types　of　LDH　on　the　corrosion　resistance　of　AZ31　alloy　were　investigated　for　the　first　time.　Detailed　morphology　and　composition　of　the　LDH/MAO　coatings　were　characterized　using　scanning　electron　microscopy　(SEM),　X-ray　diffraction　(XRD),　and　X-ray　photoelectron　spectroscopy　(XPS).　Besides,　the　corrosion　resistance　of　AZ31　alloy　with　different　LDH/MAO　coatings　was　also　tested　by　electrochemical　work　station.　The　results　from　polarization　curves　and　electrochemical　impedance　spectroscopy　indicate　that　AZ31　alloy　coated　with　Ni-LDH/MAO　has　the　higher　impedance　modulus　and　lower　corrosion　current　density　than　Zn-LDH/MAO　and　Al-LDH/MAO.　The　anti-corrosion　property　of　AZ31　alloy　covering　Ni-LDH/MAO　coating　is　remarkably　enhanced　during　long-term　immersion　in　1　M　NaCl　solution,　since　Ni-LDH　film　growing　on　the　original　MAO　coating　can　hinder　the　penetration　of　chloride　ions　and　effectively　adsorb　a　large　number　of　NO3−　to　exchange　Cl−　in　corrosion　solution.　©　2018