The present invention relates to a control device for a spark-ignition internal combustion engine provided with a cylinder pressure sensor and aims to facilitate optimal control of a combustion state even in a situation where an operating condition is variable.A predetermined combustion-related parameter whose value is uniquely determined by behavior of a change in cylinder pressure relative to a crank angle is used as a control value. Ignition timing is calculated based on the control value in accordance with a calculation rule determined according to a current or target operating condition of the internal combustion engine. The control value resulting from calculation based on a target value of a predetermined physical quantity relating to torque of the internal combustion engine in accordance with a predetermined calculation rule is used as a base value and is corrected by feeding back an output value of the cylinder pressure sensor.