PURPOSE: To prevent the unburned component from being sharply increased in exhaust gas by canister purge when the remaining amount of fuel in a fuel tank is reduced and when the fuel becomes heavy and falls in a condition in which the fuel is not easily burned.

CONSTITUTION: When the temperature Tw of cooling water exceeds a predetermined temperature (S2) and when the car velocity VSP exceeds a predetermined velocity (S3), a purge route is opened to carry out canister purge. When the remainder in a fuel tank is no less than a predetermined amount (S4), the purge route is fully opened and controlled (S6). When the remainder is less than the predetermined amount, the opening of the purge route is throttled to, for example, 80% of fully opened condition.