To provide a fuel cell energy network system and an operation method of the same capable of reducing equipment cost of the system by aiming at reduction of capacity of a fuel cell equipment.

Fuel systems and energy system of a plurality of fuel cells 11 distributed in a plurality of buildings A to G are connected to each other, and auxiliary devices, common to the fuel cells, including at least a water electrolytic device 13, a hydrogen compressor 16, a hydrogen bomb 17, an oxygen compressor 18, and a oxygen bomb 19 are put together in one machine room of one building, and power and energy are distributed to the respective buildings. When a load is low, hydrogen and oxygen, generated by the water electrolytic device 13, are compressed and stored by using the hydrogen compressor 16, the hydrogen bomb 17, the oxygen compressor 18, and the oxygen bomb 19. When the load is high, power is generated by supplying hydrogen and oxygen to the fuel cells 11 from the hydrogen bomb 17 and the oxygen bomb 19.