This study deals with a process for the recovery of hydrogen isotopes from methane (CQ4) and water (Q2O) containing tritium in the nuclear fusion exhaust gas (Q is Hydrogen, Deuterium, Tritium). Steam Methane Reforming and Water Gas Shift reactions are used to convert CQ4 and Q2O to Q2 and the produced Q2 is recovered by the subsequent Pd membrane. In this study, one circulation loop consisting of catalytic reactor, Pd membrane, and circulation pump was applied to recover H components from CH4 and H2O, one of CQ4 and Q2O. The conversion of CH4 and H2O was measured by varying the catalytic reaction temperature and the circulating flow rate. CH4 conversion was 99% or more at the catalytic reaction temperature of 650 °C and the circulating flow rate of 2.0 L/min. H2O conversion was 96% or more at the catalytic reaction temperature of 375 °C and the circulating flow rate of 1.8 L/min. In addition, the amount of CQ4 generated by Korean Demonstration Fusion Power Plant (K-DEMO) in the future was predicted. Then, the treatment process for the CQ4 was proposed and HAZOP (hazard and operability) analysis was conducted to identify the risk factors and operation problems of the process.