A characteristic of fuel cell is to convert directly into electric energy not through the heat energy. Direct carbon fuel cell (DCFC) is different from the SOFC and MCFC using the gas fuel and is for solid carbon fuel including various organic resources. The overall reaction is C+O_2→CO_2 and the theoretical conversion efficiency is close to 100%. The DCFC is useful for emergency power in the event of a disaster. In this study, the carbon rod and powder is used as the fuel, molten carbonate and mixed hydroxide as the electrolyte. To clear the power generation characteristics and the optimum conditions, the influence of the anode and the cathode shape and size were evaluated. The result shows that the reaction on the anode is important as the rate-determing step in this experiment. Additionaly, as the electrolyte, the carbonate is superior to the hydroxide to keep high performance of the powder generation.