PURPOSE: To enable an accurate non-destructive inspection by a method wherein ceramic members are joined together employing a jointing material containing a nuclide that will be radioactive with the irradiation of radiation and radiation from the nuclide made radioactive afterwards is checked to detect an unjoined part.

CONSTITUTION: A jointing material is mainly composed of a solder, inorganic adhesive or the like which has been heretofore used for a joint between ceramic members or a ceramic member and a metal member with addition of a small amount of radioactive isotope. After the joining of a ceramic member, to inspect the joined part, the joined part is irradiated with radiation and then, a radiation detecting means is scanned along the joined part. As the nuclide in the joining agent irradiated with the radiation emits radiation, the detection of the radiation enables easy and quick detection of joint deficiency (unjoined part) such as void- like deficiency which will be caused due to insufficient application of the joining agent.