Manganese dioxide powders were firstly prepared via electric pulse assisted redox method with KMnO₄ and MnSO₄ as raw material, then MnO₂/C composite materials coated with different amounts of carbon were fabricated via liquid phase sintering with glucose as a carbon source. The effect of amount of coated carbon on the morphology, structure and electrochemical properties of the MnO₂/C materials were investigated. Results show that the coated carbon could induce the transformation of crystallographic structure of MnO₂ from γ-type into α-type. Under heating conditions glucose decomposed and coated on the surface of MnO₂ particles, which could inhibit the grain growth and thus refine grains. When the preparation with the process parameters: glucose concentration was 1.5 g/L and the current density was 2 A·g^-1, the prepared MnO₂/C material presented the specific capacitance of MnO₂ of 722.2 F·g^-1, in other words, the carbon coating could increase the specific capacitance by 80%, in comparison with that of the blank ones. Furthermore, after 4000 charge-discharge cycles, the capacitance retention rate could still maintain 74.72%, displayed good electrochemical performance and cycling performance.