Direct injection engine and a start-up control method thereof

A start-up control device of a direct injection engine has a fuel injector (76) for injecting fuel into the engine; and a controller. The controller is programmed to determine the presence of a learned value for calculating on the basis thereof a fuel injection amount during start-up of the engine (10) by means of a stratified charge combustion operation; calculate the fuel injection amount on the basis of the learned value when the learned value is present, and control the fuel injector (76) to inject fuel in the compression stroke to start up the engine (10) by means of a stratified charge combustion operation; and control the fuel injector (76) to inject fuel in the intake stroke of the engine to start up the engine by means of a homogeneous combustion operation when the learned value is absent, and obtain and store the learned value during the homogeneous combustion operation of the engine.