An exhaust drain valve includes a valve casing, a primary flow passage introducing an anode-off gas and a produced water from an inlet of the primary flow passage to an inside, a secondary flow passage discharging the anode-off gas and the produced water from an outlet of the secondary flow passage to an outside, a valve seat being formed at a primary flow passage outlet, and a valve body moving forward and backward. The primary flow passage includes an orifice being communicated with the primary flow passage outlet, an introduction flow passage having a diameter larger than a diameter of the orifice, the introduction flow passage being communicable with the inlet, and a step portion being formed orthogonal to an axial direction of the introduction flow passage, the step portion connecting the orifice and the introduction flow passage by having a step between the orifice and the introduction flow passage.