A wire catalyst for hydrogenation reaction and/or dehydrogenation reaction comprises a metallic core and an oxide surface layer covering at least part of the surface thereof. The metallic core is electrically conductive so that the metallic core itself can generate heat by directly passing an electric current therethrough or electromagnetic induction. The oxide surface layer is made of an oxide of a metallic element constituting the metallic core. The oxide surface layer is provided with a porous structure having pores opening at the surface of the oxide surface layer. The catalytic material is supported in the pores of the oxide surface layer. When a shaped wire catalyst is manufactured, the shaping into a specific shape is made before the oxide surface layer having the porous structure is formed and the catalytic material is supported thereon.