An engine includes: an oil control valve built in a cylinder head, and configured to control a pressure of oil to be supplied to a variable valve mechanism via a camshaft; and a cam cap fixed to an upper face of the cylinder head, and configured to rotatably support the camshaft between the cam cap and the cylinder head, as a flow passage for the oil to be force-fed from an oil pump to the oil control valve, the cam cap including: a lateral passage formed inside the cam cap, and extended in a direction along the upper face of the cylinder head; and a downward passage extended downward from the lateral passage so as to serve as a downstream side flow passage of the lateral passage, and configured to guide the oil toward the oil control valve.