An internal combustion engine (1) automatically stops when a predetermined idle stop condition is satisfied, and automatically restarts when a predetermined idle stop cancel condition is satisfied. The internal combustion engine (1) is controlled so that when fresh air does not flow into a GPF (18) even if fuel injection is stopped during operation of a vehicle, stop of the fuel injection is permitted even when temperature of GPF (18) is high. That is, the internal combustion engine (1) is controlled so that the stop of the fuel injection is forbidden when the temperature of the GPF (18) is higher than a predetermined temperature T1 and the stop of the fuel injection is allowed when the vehicle stops in a state in which the temperature of the GPF (18) is higher than the predetermined temperature (T1).