Start-up control of in-cylinder fuel injection spark ignition internal combustion engine

An in-cylinder fuel injection internal combustion engine (1) is started up by means of compression stroke fuel injection from the beginning of cranking of the engine (1) to the end of a stratified combustion start-up period TST. If the engine (1) reaches complete combustion during the period, a warm-up operation is begun immediately. If the engine (1) does not reach complete combustion during the period, start-up of the engine (1) is continued using intake stroke fuel injection. By means of this control, stable start-up is assured while suppressing the discharge of unburned fuel during start-up of the engine (1).