An engine control device is configured to perform optimum combustion control according to environmental conditions when warming up of a catalyst for emission purification is required. The engine control device performs stratified combustion by the compression stroke injection at the time of startup, when warming up of the catalyst is required. However, under conditions of low air density, stratified combustion by compression stroke injection is prevented, and either homogenous combustion by intake stroke injection is performed, or double injection combustion by intake stroke injection and compression stroke injection is performed. Thus, the engine control device maintains starting properties and prevents adverse effects on engine operability.