A recombination device (1, 1) for catalytically recombining hydrogen and/or carbon monoxide with oxygen in a gaseous mixture comprises at least one catalyst system (2) in which a housing (4) is mounted through which the gaseous mixture can flow in free convection in the operational phase. According to the invention, said catalyst system (2) is provided with a plurality of sub-areas (T1, T2) in the direction of flow. A first sub-area (T1) comprises in the incoming direction a catalyst body (6) with a surrounding throttle layer (8) for inhibiting the diffusion of the incoming and/or discharged reaction gases. A second sub-area (T2) that adjoins the first sub-area (T1) comprises at least one catalyst body (6) that is directly accessible by the reaction gases.