To provide a method for joining ceramic structures which can exactly align the joining surfaces of small ceramic structures with each other even when numbers of the small ceramic structures are joined together to obtain a large ceramic structure, can make the thickness between surfaces to be joined uniform, can reduce the frequency of joining, and is excellent in work efficiency and an apparatus for the method.

The joining apparatus is used for joining the ceramic structures together by a joining agent. In the apparatus, a plurality of the ceramic structures 1, with the joining agent arranged between the surfaces 17 to be joined, and an elastomer sleeve 7 arranged on the circumferential surface, while an elastomer sheet 9 is arranged between the sleeve 7 and a cylindrical container 8, are installed in the container 8. In this state, a hydrostatic pressure medium is injected between the container 8 and the sheet 9, and the ceramic structures 1 are pressurized and joined together.