A curved plate for a railcar bodyshell includes: a plate main body including an outer surface facing an outside of a railcar and an inner surface facing an inside of the railcar and the plate main body having a curved shape; and reinforcing ribs projecting from the inner surface of the plate main body toward the inside of the railcar. At least two of the plurality of the reinforcing ribs include machining reference surfaces formed on a same plane as reference surfaces used when machining an outer surface of the plate main body. At least one of the plurality of the reinforcing rib includes a mounting reference surface perpendicular to one of a rail direction, a sleeper direction, and a vertical direction as a reference surface used when mounting the curved plate to the railcar.