Abstract: Ceramic coatings were produced on AZ91D magnesium (Mg) alloy by microarc oxidation (MAO) technique in three different electrolytic solutions and at different oxidation times. The morphology, microstructure and composition of oxidation coatings were investigated by scanning electron microscopy (SEM) and Xray diffraction (XRD), respectively. Moreover, the bonding strength between ceramic coatings and AZ91D Mg alloy, as well as corrosion properties of coatings prepared in different electrolytic solutions and at different oxidation times were also evaluated with an MFT4000 tester and a potentiodynamic polarization tester. The experimental results show that the surface morphologies and the compositions of oxidation coatings are different in different electrolyte systems. The corrosion resistance of AZ91D Mg alloy treated with MAO technique increases obviously. Moreover, the bonding strength between ceramic coatings and AZ91D Mg alloy oxidated for 15 min is the biggest among the prepared samples.