Apparatus for controlling internal combustion engine

An electronic control unit corrects ignition timing according to changes in an internal EGR amount accompanying actuation of a variable valve actuation mechanism used in an internal combustion engine. The electronic control unit computes a base correction amount AWTb based on an engine speed NE and an engine load ratio KL. The control unit multiplies the base correction amount AWTb by the ratio of a square number of an actual valve overlap amount realOL to a square number of a target valve overlap amount tOL, thereby computing a VVT correction amount AVVT of ignition timing. As result, the engine is easily and properly controlled based on the relationship between the state of the variable valve actuation mechanism and changes in the internal EGR amount.