A semiconductor device (1) includes: a first semiconductor chip (100); and a second semiconductor chip (200) that is stacked on the first semiconductor chip (100). The first semiconductor chip (100) includes a first wiring portion (111) of which a side surface is exposed at a side portion of the first semiconductor chip (100). The second semiconductor chip (200) includes a second wiring portion (211) of which a side surface is exposed at a side portion of the second semiconductor chip (200). The respective side surfaces of the first wiring portion (111) and the second wiring portion (211), which are exposed at the side portions of the first semiconductor chip (100) and the second semiconductor chip (200), are covered by a conductive layer (401), and the first wiring portion (111) and the second wiring portion (211) are electrically connected to each other through the conductive layer (401).