A control apparatus for a supercharged internal combustion engine, which can achieve a target torque accurately even if the target torque contains a high-frequency vibration component. The control apparatus determines a target air quantity and a target boost pressure from a target torque, operates an actuator for air quantity control according to the target air quantity, and operates an actuator for boost pressure control according to the target boost pressure. The target torque is formed to contain a low-frequency torque component that is set at all times based on a torque requirement from a driver and a high-frequency torque component that is set as necessary for a specific type of vehicle control. When the target torque contains only the low-frequency torque component, the target boost pressure is formed using a pressure component corresponding to the low-frequency torque.