Abstract: 101 Heavy Water Research Reactor (HWRR) in CIAE is the first nuclear reactor constructed in China. It was permanently shut down and is preparing for decommissioning. Since tritium concentration in the light water of spent fuel pool and wastewater tanks is high, the detritiation has to be carried out. Considering the amount and the tritium concentration of the tritiated light water in HWRR, three detritiation processes which are water distillation (WD) process and two combined electrolysis and catalytic exchange (CECE1 and CECE2) processes, were evaluated for the recovery of tritium from the wastewater. It is found that the diameter and height of CECE column are much smaller than those of WD column, and the energy consumption of the electrolyzer in CECE process is smaller than that of evaporator in WD process. With the comparison of CECE1 and CECE2 processes, the CECE2 process with natural water fed to the top of the exchange column is more suitable for the treatment of tritiated light water of HWRR.