To reduce operation noise of a injector in a fuel direct injection engine directly injecting fuel from the injector into a cylinder.

In the fuel direct injection engine E directly injecting fuel from the injector 27 into the cylinder 14, an injector fixing base part 12e formed in the cylinder head 12 and cylinder head side walls 12b, 12c are connected with connecting walls 12p, 12q. Stiffness of the injector fixing base part 12e and that of the cylinder head side walls 12b, 12c are increased by the connecting walls 12p, 12q, and thereby, the vibration attendant on fuel injection of the injector 27 is suppressed, and sound pressure of radiation sound from the cylinder head 12 can be reduced. Since the frequency of the radiation sound is increased according to increase in stiffness of the cylinder head 12, sound pressure reducing effect by a sound insulating material surrounding the engine E can be enhanced.