The challenge for the present invention is to provide a film-forming method and for forming a passivation film which can sufficiently inhibit the loss of carriers due to their recombination; and a method for manufacturing a solar cell element with the use of the method or the device. The film-forming device comprises a mounting portion 22 for mounting a film-forming object, a high frequency power source 25, and a shower plate 23 which is provided to face the film-forming object S mounted on the mounting portion 22, which introduces a film-forming gas, and to which the high frequency power source is connected and a high frequency voltage is applied. A low frequency power source 26 for applying a low frequency voltage is connected to the shower plate or the mounting portion mounting a substrate. The film-forming method is performed using the film-forming device, and the film-forming method is carried out in forming a passivation film.