A method for manufacturing a metal plate, the metal plate including a first surface and a second surface positioned on the opposite side of the first surface, may include a step of rolling a base metal having an iron alloy containing nickel to produce the metal plate. The metal plate may include particles containing as a main component an element other than iron and nickel. In a sample including the first surface and the second surface of the metal plate, the following conditions (1) and (2) regarding the particles may be satisfied.(1) The number of the particles having an equivalent circle diameter of 1 µm or more is 50 or more and 3000 or less per 1 mm³ in the sample.(2) The number of the particles having an equivalent circle diameter of 3 µm or more is 50 or less per 1 mm³ in the sample.