A fuel modification apparatus (10) is equipped with evaporators (12) for evaporating a raw fuel as a fuel to be modified, a super heater (14) for elevating the temperature of the above evaporated raw fuel to a temperature required for the modification, a modification vessel (16) for modifying the above raw fuel having an elevated temperature to form a modified gas, and a pre-heater (18) for preheating a heating fluid for evaporating the above raw fuel in the evaporator (12). The evaporators (12) are arranged on a concentric circle, surrounding the super heater (14).