To easily provide a semiconductor device using a TAB tape member which is excellent in heat-radiation effect by settling a problem of poor wettability of a heat-radiation adhesive with no change in a conventional manufacturing process for a semiconductor device.

A semiconductor device 1 comprises a semiconductor element 2, a TAB tape member 7 comprising a lead part 8 connected to an electrode part or terminal part 3 of the semiconductor element 2 using a wiring member 4, and a heat-radiation plate 9 which is, connected to a part of the semiconductor element 2 through an adhesive 10 comprising a heat-radiation adhesive, jointed together to the TAB tape member 7 with an adhesive 12 through a reinforcing plate 11 arranged with the semiconductor element 2 in between. Here, a sealing resin 13 which fits the semiconductor element 2 to the TAB tape member 7 is extended from the end part of the semiconductor element 2 as far as a position P1 where at least one end part 15 of the reinforcing plate 11 joints the TAB tape member 7.