A cylinder direct injection type internal combustion engine, including a
fuel injection device configured to directly inject a first octane-value
fuel and a second octane-value fuel into a combustion chamber. The second
octane-value fuel has an octane value larger than an octane value of the
first octane-value fuel. A controller is programmed to perform a first
operation mode. In the first operation mode, the first octane-value fuel
is injected from the fuel injection device, and the second octane-value
fuel is injected from the fuel injection device toward an ignition flame
formed by self-ignition combustion of the first octane-value fuel, so as
to cause flame propagation and combustion of the second octane-value
fuel.