A resin sealing-type semiconductor device comprises a first semiconductor chip 15 with a large amount of heat generation, whose external electrode leading-out bonding pads 16 are wire-bonded to respective outer leads 25A and a second semiconductor chip 17 smaller in the amount of heat generation than the first semiconductor chip, whose external electrode leading-out bonding pads 18 are wire-bonded to respective outer leads 25A, wherein the first semiconductor chip 15 is molded by a high thermal conductive resin 28, and the second semiconductor chip 17 and the first semiconductor chip 15 molded by the high thermal conductive resin are integrally molded by a non-high thermal conductive resin 31. A method includes manufacturing the resin sealing-type semiconductor device.