A semiconductor device (1) of the present invention includes a semiconductor element (103) including electrode parts (104), and a wiring substrate (108) including an insulation layer (101), electrode-part-connection electrodes (102) provided in the insulation layer (101), and external electrodes (107) that is provided in the insulation layer (101) and that is connected electrically with the electrode-part-connection electrodes (102), in which the electrode parts (104) and the electrode-part-connection electrodes (102) are connected electrically with each other. The insulation layer (101) has an elastic modulus measured according to JIS K6911 of not less than 0.1 GP a and not more than 5 GPa, and the electrodes (104) and the electrode-part-connection electrodes (102) are connected by metal joint.