To provide a reactor of high reaction efficiency saving power consumption capable of suppressing transfer of heat generated in a reaction zone to adjoining reaction zones, a container for housing the reactor, and to provide a reaction apparatus.

The reactor 6 comprised of a plurality of reaction zones 7 is characterized in that at least a radiant heat shield 10 is disposed between adjacent reaction zones 7. The container 12 for housing a reactor equipped with a container A for housing a reactor 6' comprised of a plurality of reaction zones 7 is characterized in that a radiant heat shield 10' is disposed between the adjacent reaction zones 7 on the inner face of the container A.