A fuel cell power generating system which is advantageous not only in that steady power supply can be achieved according to the load, but also in that the power supply can be flexibly controlled even when different types of loading apparatus utilize the electric power generated. The fuel cell power generating system includes a fuel cell power generating apparatus (10) for electrochemically reacting a predetermined fuel, such as hydrogen or methanol, and air to allow a power generator to generate electric power, and a loading apparatus (20) connected to the fuel cell power generating apparatus (10) through a predetermined electric cable (30) for supplying the electric power generated by the fuel cell power generating apparatus. The fuel cell power generating apparatus (10) receives loading apparatus power information on electric power required for the loading apparatus (20) through the electric cable (30) upon supplying the electric power to the loading apparatus (20) through the electric cable (30), and controls power generation according to the loading apparatus power information received.