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Using the unbalanced magnetron sputter ion plating technique graphite-like coatings with Al, Zr and W as transition layers on the surface of magnesium substrate were prepared. The section microstructure and phase composition of the coatings were analyzed by TEM and the binding force and tribological performance were tested by a scratch tester and a wear machine. The results show that a mixing layer with magnesium and β-Mg17Al12 phase is formed in the interface between Al transition layer and magnesium substrate; there is a partial continuous interface between Zr transition layer and magnesium substrate; the interface between W transition layer and magnesium substrate is a mixed interface layer with magnesium phase and tungsten clusters of about 20nm because of the implantation of tungsten particles into magnesium substrate. The binding force of the three kinds of doped (aluminum, zirconium, tungsten) carbon coatings on the surface of magnesium substrate is 10.2, 11.0 and 4.8 N, respectively. The different work layers of three kinds of doped carbon coatings result in different wear-resistant and anti-friction performances. The Al-doped carbon coating has low friction between 0.1~0.18, so its wear resistance is good and the coating will not fail even after the ball-disc experiment. The work layer of zirconium-doped carbon coating fails around 1600 s when the friction coefficient begins to increase sharply. Its friction coefficient is between 0.08~0.18 before the failure, and it has good wear-resistant and anti-friction performance. The friction coefficient of the tungsten doped carbon coating increases dramatically from the beginning and the coating fails completely in 250 s with a large area of spalling; therefore its wear and friction reducing effect among the three coatings is the worst