A ventilator has incorporated in a main body thereof an air blower having a ventilation casing provided with a fan intake opening facing an intake opening of the main body of the ventilator, the inner side of the main body being opened to form the intake opening thereof. A cylindrical soundproof unit including an inner ventilation passage having a larger ventilation area than a fan intake space and formed of a laminated plate which is formed of a plurality of air layers arranged in a direction intersecting the rotation axis of the air blower from the inner ventilation passage, is disposed in a space between the fan intake opening and the intake opening of the main body. The soundproof unit makes it possible to decrease noise generated by the air blower while the ventilation resistance is hardly increased.

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