Tritium must be strictly defended in tritium systems because of its permeability and radioactivity. Detritiation devices are required in tritium systems, such as the glove box detritiation system, the vent detritiation system, and the air detritiation system in ITER. The method of catalytic oxidation and adsorption is widely used for air detritiation, and metal gas getter is used in glove box detritiation. Here, a Ce-based oxide-loaded honeycomb catalyst is prepared as a multifunctional detritiation catalyst. The properties of the Ce-based oxide and catalyst are characterized by X-ray diffraction, N2-adsorption/desorption (Brunauer-Emmet-Teller method), and H2 temperature programmed reduction. The catalytic performance is tested under both O2-lean and O2-rich atmospheres. Results indicate that the Pt/Ce0.7Zr0.3O2 honeycomb catalyst fully oxidizes H2 at room temperature with high space velocity (3.2 × 104 h−1) when oxygen is sufficient. When oxygen is deficient, H2 is also fully oxidized by the catalyst at 200°C, with the oxygen supplying from the support. A detritiation test using tritium as reactant is also carried out, and the results verify the feasibility for detritiation application. An improved detritiation reactor is designed and built based on the multifunctional catalyst.