To provide a multi-cylinder four-cycle engine that ensures sufficient ventilation capacity in a cylinder head cover with no need of providing a separate ventilation case.

In a multi-cylinder four-cycle engine, intake air passing through an air cleaner is supplied to each cylinder from a surge tank 16 through an intake manifold 19, and blowby gas is introduced into the surge tank 16 through a cylinder head cover 15. In this configuration, the cylinder head cover 15 and the surge tank 16 are integrated to eliminate a gap therebetween. Therefore, a sufficient ventilation capacity can be secured in the cylinder head cover 15, eliminating a separate ventilation case.