<p>A gas separating body is disclosed which comprises a porous base composed of a first ceramic and a gas separating layer containing zeolite which is arranged on the surface of the base. The gas separating layer contains, in addition to zeolite, a thermal expansion coefficient-regulating material which is composed of a second ceramic having a thermal expansion coefficient satisfying a predetermined relation so that the difference of thermal expansion coefficient with the porous base can be reduced. The gas separating body can be preferably used particularly when carbon dioxide (CO2) or the like is selectively separated from a mixed gas such as natural gas.</p>
