To provide an expansion and contraction joint and a connection structure which can be easily manufactured and can hold vacuum airtightness of a piping system, to provide a method for manufacturing the expansion and contraction joint and to provide a method for manufacturing the connection structure.

The expansion and contraction joint 10 includes a bellow 11 made of a metal which has a cylindrical shape whose wall surface has a bellow structure, can be expanded and contracted in an axial direction and connection parts 12, each of which has a plate shape having a center hole and made of a metal different from that of the bellow 11 and which are airtightly formed on end parts of the bellow 11. The expansion and contraction joint 10 can be connected to the piping by welding or brazing by forming the connection part 12 from a metal, the same metal that constitutes the piping and the like connected by the expansion and contraction joint 10.