A spark ignition-type internal combustion engine of the present invention is provided with a variable compression ratio mechanism able to change a mechanical compression ratio, a variable valve timing mechanism able to control a closing timing of an intake valve, and an EGR mechanism feeding part of the exhaust gas through the EGR passage as EGR gas into a combustion chamber. In the spark ignition type internal combustion engine, at the time of engine low load operation, compared with at the time of engine high load operation, the mechanical compression ratio is made higher. The higher the EGR rate, the higher the actual compression ratio is made.