A method for manufacturing an organic device 10 according to an embodiment includes: a film forming step of continuously forming first to N-th layers (N is an integer of 2 or more) on a first electrode layer 14 formed on a main surface 12a of a flexible substrate while continuously conveying the flexible substrate 12, wherein in the film forming step, the first to N-th layers are sequentially formed on the first electrode layer by supplying materials of the first to N-th layers from first to N-th film forming sources to the flexible substrate through first to N-th shielding parts arranged between the first to N-th film forming sources and the flexible substrate, the first to N-th shielding parts are fixed in a conveyance direction of the flexible substrate in a state of being spaced apart from the flexible substrate, and a shielding area due to at least one shielding part of the first to N-th shielding parts is different from a shielding area due to other shielding part.