To suppress generation of smoke while reducing combustion noise by a pilot injection in a compression ignition internal combustion engine performing pilot injection.

This compression ignition internal combustion engine performing pilot injection is provided with a piston 4, a main cavity which is a cavity provided on a crown part of the piston 4 and in which injected fuel by main injection is sucked, and a trap cavity 14b which is a cavity provided around an opening part edge part of the main cavity 14a and retains injected fuel by pilot injection under liquid or liquid-gas mixed condition.