Supply a control device for an internal combustion engine in which an abnormality of an exhaust-bypass valve, such as a WGV, can be certainly detected under wide operation conditions. In the control device, a required-operation position of the exhaust-bypass valve, which is set in accordance with an operating condition of the internal combustion engine, is set to a target position, and an exhaust-bypass-valve-driving device is controlled in such a way that a real position, which is detected by a position sensor, agrees with the target position, and when a real position, which is detected by a position sensor, reaches a predetermined abnormality-judgment value, it is judged that an abnormality is caused in a mechanical-connecting condition from the exhaust-bypass valve to the exhaust-bypass-valve-driving device.