Provided are a support for supporting a metal, a metal-supported catalyst, a methanation reaction apparatus, and a method relating thereto that realize effective methanation of carbon monoxide. The support for supporting a metal includes a carbonized material obtained by carbonizing raw materials containing an organic substance and a metal, in which the support is used for supporting a metal that exhibits a catalytic activity for a methanation reaction of carbon monoxide. The metal-supported catalyst includes : a support formed of a carbonized material obtained by carbonizing raw materials containing an organic substance and a metal; and a metal that exhibits a catalytic activity for a methanation reaction of carbon monoxide, the metal being supported on the support.