The present invention is a method of manufacturing a light emitting display panel, which includes a laminated structure formed by laminating at least a flexible base layer, a first electrode layer, an EL layer, a second electrode layer and a flexible sealing layer in that order. The flexible base layer is provisionally attached to a rigid flat plate, and thereafter supplied to a main manufacturing step of the light emitting display panel. According to the feature, no significant unevenness in the thicknesses of layers formed on or above the flexible base layer is generated. Therefore, a light emitting display panel whose light emitting strength is uniform can be produced.