A fluidized bed electrode could lower concentration polarization and activation polarization because of its high mass and heat transfer coefficient. The polarization characteristics of the fluidized bed electrode are systematically investigated in a molten carbonate fuel cell anode with an O2/CO2/gold reference electrode. The results show that polarization performance of the anode is improved by selecting proper flow rates of H2, O2 and CO2, choosing suitable nickel particle content together with appropriate O2/CO2 ratio, and increasing reaction temperature as well as the area of the current collector. Limiting current density of 115.56 mA·cm^(-2) is achieved under optimum performance as follows: a cylindrically curved nickel plate current collector, nickel particle content of 7.89%, the reaction temperature of 923 K, H2 flow rate of 275 mL·min^(-1), O2/CO2 flow rate of 10/20 mL·min^(-1) and O2/CO2 ratio of 1 : 2.