There is provided a joined body formed by unitarily joining two or more members to be joined by means of a bonding material layer formed of a bonding material composition. The bonding material composition contains flat particles, non-flat particles, and an inorganic adhesive as main components, and the bonding material layer has a Young's modulus of 3 GPa or more. The joined body can suppress deformation of members to be joined due to thermal distortion with the bonding material layer, hardly causes rupture of the bonding material layer due to stress, and has excellent thermal shock resistance.