PURPOSE: To appropriately supply evaporative fuel to an engine even when heat damage is generated or even when the opening of a throttle valve is small by controlling the operation of a purge valve so that the amount of evaporative fuel from a canister is controller in accordance with the fuel residual amount in a fuel tank.

CONSTITUTION: Evaporative fuel adsorbed and held to a canister 16 is supplied into an engine 4 in accordance with the opening state of a throttle valve 10. A purge valve 26 is provided on the way of a purge passage 20 between the canister 16 and an air-intake passage 22. And a control means 28 for controlling the operation of the purge valve 26 is provided so as to control the amount of evaporative fuel from the canister 16 in accordance with the fuel residual amount in a fuel tank 12. Accordingly, the evaporative fuel from the canister 16 is eliminated in accordance with the fuel residual amount in the fuel tank 12. Therefore, the evaporative fuel can be appropriately supplied into the engine 4, moreover, the purge performance of the canister 16 ca be improved even when heat damage is generated or even when the opening of the throttle valve 10 is small.