<p>Current density (CD) played a critical role in the performance of micro–arc oxidation (MAO) coatings on magnesium (Mg) alloy, which influenced their tribocorrosion and electrochemical properties. In this study, MAO coatings were prepared under the different current densities on AZ31B Mg alloy, and their tribocorrosion and electrochemical behaviors in 3.5% NaCl solution were evaluated to elucidate the wear and corrosion mechanisms. The results demonstrate that the average coefficients of friction (COFs) are increased with the CD, whereas the wear rates are opposite. The MAO coating prepared at 6 A•dm^–2 has the lowest wear rate, demonstrating the enhanced tribocorrosion performance. The abrasive wear and oxidative wear dominate the wear mechanism, which are correlated with the increased hardness by the optimal CD. Moreover, the MAO coating prepared at 5 A•dm^–2 with the lowest corrosion current density exhibits superior anti–corrosion performance.</p>