Internal combustion engine provided with camshaft-driven accessory

An internal combustion engine has a camshaft holder attached to a cylinder head , and two camshafts and are rotatably supported by the camshaft holder . A high-pressure pump has a driving shaft rotatively driven by the camshaft. An accessory holder provided with a mounting seat to which the high-pressure fuel pump is attached is formed integrally with a lower camshaft holder included in the camshaft holder . The mounting seat is formed integrally with the accessory holder and is provided with a through hole in which the driving shaft is received. Thus the cylinder head is formed in a small size and a light weight. The accessory holder can be formed with a high rigidity in a small size.