Internal combustion engine, comprising: - a turbocharger provided with a waste gate valve that is a swing-type waste gate valve; - an actuator that is configured to control an opening degree of the waste gate valve; - a supercharging pressure sensor that is configured to detect supercharging pressure; - a temperature sensor that is configured to detect a temperature state of the internal combustion engine; and - a waste gate valve control device that comprises a control section that is configured to output a target opening degree of the waste gate valve based on the supercharging pressure detected by the supercharging pressure sensor, at a time of non-idling of the internal combustion engine; characterized in that the control section is configured to: - execute regular opening control for supercharging pressure control in case where an accelerator opening degree is not at a threshold value (APOO) or less; - set the target opening degree of the waste gate valve to full opening, during idling after warm-up of the internal combustion engine, where the accelerator opening degree is at the threshold value (APOO) or less, an engine rotation speed (Ne) of the internal combustion engine is at a threshold value or more and a cooling water temperature is at a threshold value or higher, and when the accelerator opening degree is not in a sudden deceleration state, wherein, when the rotation speed (Ne) of the internal combustion engine is at the threshold value or more, the start of the internal combustion engine is completed; - set the target opening degree of the waste gate valve to full opening in case where the accelerator opening degree is at the threshold value (APOO) or less and the engine rotation speed (Ne) of the internal combustion engine is lower than the threshold value; and - set the target opening degree of the waste gate valve to an intermediate opening degree and output it during idling in an engine cold state, where the accelerator opening degree is at the threshold value (APOO) or less, the engine rotation speed (Ne) of the internal combustion engine is at the threshold value or more and the cooling water temperature is lower than the threshold value, wherein the intermediate opening degree is smaller than the full opening degree. - a turbocharger provided with a waste gate valve that is a swing-type waste gate valve; - an actuator that is configured to control an opening degree of the waste gate valve; - a supercharging pressure sensor that is configured to detect supercharging pressure; - a temperature sensor that is configured to detect a temperature state of the internal combustion engine; and - a waste gate valve control device that comprises a control section that is configured to output a target opening degree of the waste gate valve based on the supercharging pressure detected by the supercharging pressure sensor, at a time of non-idling of the internal combustion engine; - execute regular opening control for supercharging pressure control in case where an accelerator opening degree is not at a threshold value (APOO) or less; - set the target opening degree of the waste gate valve to full opening, during idling after warm-up of the internal combustion engine, where the accelerator opening degree is at the threshold value (APOO) or less, an engine rotation speed (Ne) of the internal combustion engine is at a threshold value or more and a cooling water temperature is at a threshold value or higher, and when the accelerator opening degree is not in a sudden deceleration state, wherein, when the rotation speed (Ne) of the internal combustion engine is at the threshold value or more, the start of the internal combustion engine is completed; - set the target opening degree of the waste gate valve to full opening in case where the accelerator opening degree is at the threshold value (APOO) or less and the engine rotation speed (Ne) of the internal combustion engine is lower than the threshold value; and - set the target opening degree of the waste gate valve to an intermediate opening degree and output it during idling in an engine cold state, where the accelerator opening degree is at the threshold value (APOO) or less, the engine rotation speed (Ne) of the internal combustion engine is at the threshold value or more and the cooling water temperature is lower than the threshold value, wherein the intermediate opening degree is smaller than the full opening degree.