A hydraulic orifice which is mounted at a head oil journal formed in a cylinder head and supplies an oil to a supply line after reducing pulsation of the oil supplied to the head oil journal, may include a body pressed on the head oil journal so as to form a chamber with the cylinder head, a joining line formed along a longitudinal axis of the body therein and fluid-communicating with the supply line, and at least two hydraulic lines formed in the body and connecting the chamber with an end of the joining line in the body to supply the oil through the other end thereof to the supply line, wherein the oils passing through the at least two hydraulic lines are joined at the end of the joining line with different phases such that the pulsation of the oil in the joining line is reduced.