Provided is a hydrogen-recycling MCFC power-generating system that can improve power generation efficiency by effectively utilizing fuel gas having the hydrogen included in anode exhaust as the main component, and that can reduce the amount of carbon dioxide discharged by separating and recovering the carbon dioxide. The system is provided with a molten carbonate fuel cell (9), a carbon dioxide separating system (20) that separates and recovers a portion of the carbon dioxide from the anode exhaust (AE) from the fuel cell, a gas mixer that mixes recycled fuel gas (RF) after a portion of the carbon dioxide has been separated from the anode exhaust with new fuel gas (F) that is supplied from outside to make a mixed fuel gas (MF), a fuel gas heater (13) that diverts a portion of the mixed fuel gas, preheats it to a constant temperature and adds reforming steam (STM), and a multistage pre-converter (14) that performs a reforming reaction and a methanation reaction of the mixed fuel gas simultaneously. The mixed fuel gas exiting the multistage pre-converter is supplied to the anode (A) of the fuel cell.