A quenching apparatus that sprays a cooling fluid to quench a metallic material, comprising: a defoaming apparatus that removes air bubbles from the cooling fluid, a supply bath that accumulates the cooling fluid thatair bubbles has been removed, and a cooling apparatus that sprays the cooling fluid that has been supplied from the supply bath toward the metallic material; the defoaming apparatus comprising: a defoaming bath, and a circulation apparatus that recovers the cooling fluid that has been used for quenching, and supplies the cooling fluid to the defoaming bath; wherein: the defoaming bath includes a laminar flow weir that partitions the defoaming bath into a laminar flow bath and a shallow bath, in that the laminar flow weir is lower than a side wall of the laminar flow bath, and the cooling fluid from the circulation apparatus is supplied to the laminar flow bath, and the cooling fluid that flows over the laminar flow weir from the laminar flow bath is poured into the shallow bath, the shallow bath including: a bottom portion having an opening, and a plate-shaped or sheet-shaped filter that covers the opening and has a mesh structure, wherein: a liquid level height in the shallow bath is less than a height of the laminar flow weir, and the supply bath accumulates the cooling fluid that has passed through the filter. a defoaming apparatus that removes air bubbles from the cooling fluid, a supply bath that accumulates the cooling fluid thatair bubbles has been removed, and a cooling apparatus that sprays the cooling fluid that has been supplied from the supply bath toward the metallic material; the defoaming apparatus comprising: a defoaming bath, and a circulation apparatus that recovers the cooling fluid that has been used for quenching, and supplies the cooling fluid to the defoaming bath; wherein: the defoaming bath includes a laminar flow weir that partitions the defoaming bath into a laminar flow bath and a shallow bath, in that the laminar flow weir is lower than a side wall of the laminar flow bath, and the cooling fluid from the circulation apparatus is supplied to the laminar flow bath, and the cooling fluid that flows over the laminar flow weir from the laminar flow bath is poured into the shallow bath, a defoaming bath, and a circulation apparatus that recovers the cooling fluid that has been used for quenching, and supplies the cooling fluid to the defoaming bath; the defoaming bath includes a laminar flow weir that partitions the defoaming bath into a laminar flow bath and a shallow bath, in that the laminar flow weir is lower than a side wall of the laminar flow bath, and the cooling fluid from the circulation apparatus is supplied to the laminar flow bath, and the cooling fluid that flows over the laminar flow weir from the laminar flow bath is poured into the shallow bath, the shallow bath including: a bottom portion having an opening, and a plate-shaped or sheet-shaped filter that covers the opening and has a mesh structure, wherein: a liquid level height in the shallow bath is less than a height of the laminar flow weir, and the supply bath accumulates the cooling fluid that has passed through the filter. a bottom portion having an opening, and a plate-shaped or sheet-shaped filter that covers the opening and has a mesh structure, a liquid level height in the shallow bath is less than a height of the laminar flow weir, and the supply bath accumulates the cooling fluid that has passed through the filter.