Press working method and press working apparatus

A press working apparatus configured to manufacture, by press working on a film material made of resin, a resin film having a passage hole through which a fluid for a fuel cell flows, comprising a first die and a second die arranged to face each other,

• the first die comprising:
• a primary die on which the film material is placed;
• a secondary die disposed outside the primary die and vertically movable with respect to the primary die;
• and
• a first biasing member configured to bias the secondary die toward the second die,
• the second die comprising:
• a piercing punch for punching out the film material to form the passage hole in the film material;
• a holder disposed outside the piercing punch and vertically movable with respect to the piercing punch;
• and
• a second biasing member configured to bias the holder toward the first die,
• wherein the secondary die and the holder are configured to grip an outer peripheral portion of the film material together, and
• wherein the press working apparatus is configured to be out of contact with an upper surface of the film material in an adjacent portion surrounding a portion to be punched out by the piercing punch.