The present invention provides a joined body having a first member 7, a second member 4 and a joining material 14 interposed between the first and second members. The joining material has a porous bone structure 15 with open pores and made of a sintered product of metal powder and impregnated phase 10 impregnated into the open pores. The impregnated phase 10 includes an oxynitride glass. The joined body has improved resistance against fatigue and fracture, even when the body is subjected to thermal cycles between high and room temperatures and held at a high temperature over a long period of time.