A punching apparatus forms a hole at a bottom portion of each of recesses which are formed in a metal plate in advance and arrayed in a first direction. A female die supports the metal plate. A male die is opposed to the recess and provided with a punch array in which a plurality of punches in the first direction. The male die is movable in a second direction perpendicular to the first direction to form the hole with each of the punches. The punches include first punches each having a distal end face which is slant in the second direction. A slant angle of the distal end face corresponds to a warp of the plate member due to the formation of the recesses.