A control device that is used with an internal combustion engine and capable of exercising torque control by operating a throttle for adjusting an intake air amount and by making ignition timing adjustments, the control device comprising: demanded torque setup means which sets a demanded torque; demanded efficiency setup means which sets a demanded efficiency, wherein the efficiency is related to the rate of conversion of energy retained by an in-cylinder air-fuel mixture to torque, and expressed by a dimensionless value referenced to the rate of conversion at a MBT ignition timing; calculation means which calculates a demanded torque for throttle operation by dividing the demanded torque by the demanded efficiency; demanded air amount calculation means which calculates a demanded air amount by converting the demanded torque for throttle operation to the demanded air amount based on a relationship between a torque and an air amount at the MBT ignition timing under current values of operating conditions including engine speed, air-fuel ratio, and valve timing; throttle operation amount calculation means which calculates an operation amount of the throttle in accordance with the demanded air amount; ignition timing retard amount calculation means (14, 16, 18) which calculates a torque that is generated when the throttle is operated by the operation amount at a predetermined ignition timing setting, and calculates an ignition timing retard amount that is necessary to achieve the demanded torque in accordance with the ratio of the demanded torque to the calculated torque; and demanded efficiency correction means which, when a setting of the demanded torque that is generated by the demanded torque setup means rapidly increases by an amount greater than a predetermined increase amount which is a torque increase amount achievable by operating the throttle alone or at a rate higher than a predetermined increase rate which is a torque increase rate achievable by operating the throttle alone, temporarily decreases a setting of the demanded efficiency in accordance with the rapid increase in the setting of the demanded torque. demanded torque setup means which sets a demanded torque; demanded efficiency setup means which sets a demanded efficiency, wherein the efficiency is related to the rate of conversion of energy retained by an in-cylinder air-fuel mixture to torque, and expressed by a dimensionless value referenced to the rate of conversion at a MBT ignition timing; calculation means which calculates a demanded torque for throttle operation by dividing the demanded torque by the demanded efficiency; demanded air amount calculation means which calculates a demanded air amount by converting the demanded torque for throttle operation to the demanded air amount based on a relationship between a torque and an air amount at the MBT ignition timing under current values of operating conditions including engine speed, air-fuel ratio, and valve timing; throttle operation amount calculation means which calculates an operation amount of the throttle in accordance with the demanded air amount; ignition timing retard amount calculation means (14, 16, 18) which calculates a torque that is generated when the throttle is operated by the operation amount at a predetermined ignition timing setting, and calculates an ignition timing retard amount that is necessary to achieve the demanded torque in accordance with the ratio of the demanded torque to the calculated torque; and demanded efficiency correction means which, when a setting of the demanded torque that is generated by the demanded torque setup means rapidly increases by an amount greater than a predetermined increase amount which is a torque increase amount achievable by operating the throttle alone or at a rate higher than a predetermined increase rate which is a torque increase rate achievable by operating the throttle alone, temporarily decreases a setting of the demanded efficiency in accordance with the rapid increase in the setting of the demanded torque.