A rigid-flexible substrate includes a plurality of rigid portions, and a flexible portion connecting the plurality of rigid portions and including a portion of a first resin sheet including at least one layer of a thermoplastic resin sheet, the rigid portions including a portion of the first resin sheet other than the flexible portion, and a second resin sheet including a plurality of thermoplastic resin sheets laminated on one surface or both surfaces of the portion of the first resin sheet other than the flexible portion, and a tapered portion is provided at an end edge of the second resin sheet on a side close to the flexible portion, and a thickness of the tapered portion in a direction in which the second resin sheet is laminated decreases toward the flexible portion and is substantially 0 at a position in contact with the flexible portion.