A control device for an internal combustion engine in which an exhaust purification device is provided the control device controls the air-fuel ratio of exhaust gas flowing into an exhaust purification device when the temperature of a three-way catalyst belongs to a temperature range in which it is not less than an activation onset temperature and is less than an activation complete temperature. The control device controls the air-fuel ratio of exhaust gas flowing into the exhaust purification device to a first air-fuel ratio which is lower than or equal to a theoretical air-fuel ratio when the temperature of the three-way catalyst belongs to a low-side temperature region, and controls the air-fuel ratio of exhaust gas flowing into the exhaust purification device to a second air-fuel ratio which is higher than the theoretical air-fuel ratio when the temperature of the three-way catalyst belongs to a high-side temperature region.