An intake control system for an internal combustion engine is capable of ensuring a differential pressure across an EGR valve, and controlling an EGR amount with high accuracy. A target fresh air amount is set based on a demanded torque calculated according to operating conditions of the engine. A differential pressure across an EGR valve is set as a target differential pressure. When it is determined that the across-valve differential pressure is not in a state in which the target differential pressure can be ensured, an opening degree of the EGR valve is controlled to limit an EGR amount. An opening degree of a throttle valve is controlled based on the target fresh air amount, so as to ensure the target differential pressure.