To reduce an amount of oil flowing into tappet holes on both sides of the bearing part, which oil has been blown out of an radial oil port of a camshaft toward a bearing part and thereby to improve lubricity of the bearing part.

In lubrication structure for a valve gear, a pair of valves is disposed each cylinder of an engine. A camshaft having cams corresponding to the pair of valves are journaled to a cylinder head through bearing parts formed in a cylinder head and a cam cap. A bearing part is disposed between a pair of valves, oil is supplied in an axial center oil passage extended from the oil supply source in an axial center direction of the camshaft, and the bearing part is lubricated by radial oil ports communicating with the axial center oil passage, extending in a radial direction of the camshaft, and opening to the bearing part. Each radial oil port of the camshaft is formed by avoiding a line in a direction of the maximum diameter of the cam passing a top part of the cam of each cylinder and the axial center of the camshaft.