A substrate (10) having a built-in component is provided with a cavity in a laminated body formed by laminating flexible resin sheets (201-205), said cavity being configured from through holes (231, 241) that penetrate the resin sheets (203, 204). In the cavity, a chip-type electronic component (30) which is provided with external electrodes (31, 32) is disposed. The resin sheet (202) having the chip-type electronic component (30) disposed thereon is provided with through holes filled with a conductive paste (521P, 522P). Furthermore, the resin sheet (203) is provided with cutouts (2321, 2322) that communicate with the through hole (231), and are disposed at a distance with the through hole (231) therebetween. Though the conductive paste (521P, 522P) protrudes from the through holes when the laminated body is hot pressed, the protruded conductive paste (521P, 522P) enters the cutouts (2321, 2322).