Catalytic hydrogen evolution from neat tetrahydronaphthalene under liquid-phase conditions was investigated. Among examined commercial Pd-, Pt-, and Rh-catalysts supported on activated carbon or alumina, Pd/C showed the highest activity. It was also found that Pd-catalysts supported on activated carbon fibers, which were prepared by an impregnation method, showed roughly three times higher activity than that of the commercial Pd/C.