A catalyst structure that allows prevention of aggregation of fine particles of a functional substance, suppresses decrease of catalyst activity, and thus enables extension of the lifetime of the catalyst structure. A catalyst structure has a carrier that is formed from a zeolite-type compound and has a porous structure. The functional substance includes a first element that is at least one metallic element selected from the group consisting of cobalt (Co), nickel (Ni), iron (Fe), and ruthenium (Ru), and at least one second element selected from the group consisting of metallic elements in group 1, group 2, group 4, group 7, and group 12 on the periodic table. The carrier has paths connected to each other. The functional substance is present in at least the paths of the carrier.