Apparatus for manufacturing glass sheet and method for manufacturing glass sheet

This apparatus for manufacturing a glass sheet comprises: a float bath for accommodating a molten metal; an annealing furnace into which a glass ribbon molded into a sheet shape is carried on the molten metal; a chamber provided between the float bath and the annealing furnace; and a plurality of lift-out rolls for conveying the glass ribbon from the float bath to the annealing furnace, the lift-out rolls being provided inside the chamber. This apparatus for manufacturing a glass sheet is configured so that a first ventilation unit for supplying an inert gas as a cooling gas is provided inside the chamber in a space disposed downstream from the point of contact between the glass ribbon and the farthest downstream lift-out roll, the space being part of a space below the glass ribbon.