To obtain a fuel cell bipolar plate of high quality and high productivity with less deformation, warpage, and cracking at the time of product removal from a die by making equal the density balance between a gas flow passage groove part area and a surrounding part area on the surface of the bipolar plate.
A (upper) lower inner die (42,) 22 is positioned at a prescribed height (under or) above a (upper) lower outer die (45,) 25 so that the compression ratio of a flow passage groove part 2 and the compression ratio of a surrounding part 4 are equal when a cavity 50 formed between upper and lower dies 41 and 21 divided into the upper and lower inner dies 42 and 22 corresponding to the flow passage groove part 2 and the upper and lower outer dies 45 and 25 corresponding to a surrounding part 4, respectively, is filled with a powder-like material. The upper and lower outer dies 45 and 25 are projected with respect to the upper and lower inner dies 42 and 22 so that the flow passage groove part 2 is released from the die preceding to the surrounding part 4 on each of the front and rear surfaces at the time of die opening for molded product removal after compression molding.