Micro-arc　oxidation(MAO)　coatings　with　different　thickness　(10　μm,　15　μm　and　20　μm)　were　deposited　on　LD10　Al　alloy　samples　using　MAO　processing.　The　samples　were　tested　using　a　rotating　bending　fatigue　tester　to　character　their　fatigue　properties.　Scanning　electron　microscopy　(SEM)　was　used　to　observe　the　microstructure　and　fatigue　fracture　morphology　of　the　specimen　with　MAO　coatings.　X-ray　diffraction　(XRD)　was　employed　to　analyze　the　phases　and　residual　stress　in　the　coatings.　The　results　show　that　the　MAO　coating　is　mainly　composed　of　AlSi0.5O2.5　amorphous　phase,　and　the　net　micro-cracks　observed　in　the　coating　initiate　in　the　discharge　channel　and　end　at　the　region　near　the　discharge　channel.　The　tensile　residual　stress　presented　at　the　interface　of　the　substrate　and　the　coating　induces　early　crack　initiation　and　propagation.　Compared　to　the　sample　without　MAO　coating,　the　reduction　of　fatigue　life　are　63%,　75%　and　65%,　and　the　reduction　of　fatigue　limit　are　9.5%,　7.9%　and　9.9%　for　the　samples　with　the　MAO　coatings　thickness　of　10μm,　15μm　and　20μm,　respectively.