Molten carbonate fuel cell (MCFC) has been extensively studied and vigorously developed. However, the shortage in gas-diffusion electrode limits its widely application to a large extent. Fluidized bed electrode (FBE) has been paid more and more attention all around the world due to its high mass and heat transfer coefficient. In this study, a novel fuel cell combined MCFC and FBE is proposed, which is called fluidized bed electrode fuel cell (FBEFC). Its polarization characteristics are fundamentally investigated under various experimental conditions. The optimal performance of the FBEFC is obtained under the following conditions with an open circuit voltage of 0.987V and a peak power density of 39.6mWcm(-2): electrolyte composition, 62% Li2CO3: 38% K2CO3; O-2/CO2 ratio, 1/2; reaction temperature, 923K; anode gas flow rate, 402mlmin(-1); and cathode gas flow rate, 1723mlmin(-1