A control device of an internal combustion engine calculates ignition delays in lean combustion and rich combustion, standardizes the ignition delays based on ignition timing, and further standardizes the ignition delays based on injection quantity and injection timing of pilot injection respectively. The control device calculates a present ignition delay by linear interpolation of the standardized ignition delays in the lean combustion and the rich combustion. Moreover, the control device corrects the present ignition delay with the ignition timing and further corrects the present ignition delay with the injection quantity and the injection timing of the pilot injection. The control device calculates a command value of the injection timing by subtracting the corrected present ignition delay from target ignition timing.