An exhaust gas guide member is provided to an airflow control valve varying an opening area of an intake passage. The exhaust gas guide member forms an exhaust gas passage which introduces the exhaust gas flowing from the exhaust gas introducing portion into the intake pipe toward an opposite end of the airflow control valve relative to the valve shaft. Thereby, the exhaust gas flows together with an intake air flow of high velocity generated by the airflow control valve so that a tumble flow can be generated in a combustion chamber of the internal combustion engine.