To provide an orifice member which dispenses with a member for replacement and which can restrict the flow of rainwater etc., and a pit equipped with the orifice member.

This orifice member 10, which is provided on the inflow port-side or outflow port-side of the pit, restricts the flow of the water flowing inside and outside the pit. The orifice member 10 is equipped with a cut portion 20 which can be cut off in different positions and in which a circulation portion having an opening area varied by changing the cut-off positions can be formed. The cut portion 20 is formed in an approximately conical shape. A plurality of gauge lines 40, which are arranged toward a leading end side from a base side and each elongated in a peripheral shape, are provided on the surface of the cut portion 20.