In order to develop the more compact and more cost-effective tritium removal system for the fusion reactor, the new system of using gas separation membrane has been studied in Tritium Process Laboratory (TPD/Japan Atomic Energy Research Institute (JAERI). To apply the scaled polyimide membrane module (hollow filament type) to the secondary confinement system, the basic-tritium recovery performance was summarized as a module itself from N2, air, Ar mixture, and recoveral performance was well demonstrated from existing glovebox (1.4 m3 : GB). The tritium recovery performance of the membrane module was well analyzed as a cross flow model, and removal from actual GB results was well simulated by the stand-alone performance data. Using this membrane module performance, new detritiation system was designed for the secondary confinement (GB).