The purpose of the present invention is to provide a circuit-embedded substrate in which electrical
conductivity is not readily reduced, and a method for manufacturing a circuit-embedded substrate in which such a circuit-embedded substrate can be easily manufactured. The purpose of the present invention is also to provide a circuit-embedded-substrate integrally molded article using a circuit-embedded substrate of which the electrical
conductivity is less likely to decrease. The circuit-embedded substrate is provided with: a film; and a circuit having a functional part, a first wiring part, a second wiring part, and a folded part, the functional part, the first wiring part, and the second wiring part being embedded in the film, the functional part comprising one
metal thin wire and having an arbitrary pattern, the first wiring part being drawn out from one of both ends of the functional part, the second wiring part being drawn out from the other of both ends of the functional part, and the folded part being drawn out from the other of both ends of the functional part. The second wiring part is led out from the other of the two ends of the functional part, and the folded-back part extends from the first wiring part and the second wiring part to the side opposite to the functional part and is folded back in a mode of being parallel to the film; and two
electrode pads fixed to the first wiring portion and the second wiring portion, respectively, and electrically connected to the folded-back portion on the upper surface.