A control system reduces the amount of fuel injected from a second fuel injector in one cycle to an amount smaller than a second basic injection amount according to operating conditions of an internal combustion engine, and increases the amount of fuel injected from a first fuel injector in one cycle to an amount larger than a first basic injection amount according to operating conditions of the engine, during a predetermined period after a flow restricting operation is finished, so as to reduce fluctuations in the air-fuel ratio due to fluctuations in the wall temperature.