Abstract: The article focused the basic principles, main content, the technological process and advantages of closure low-level radioactive waste water system for many years in recovery and reconstruction process. The system retained the original coagulation, vermiculite adsorption and ion exchange treatment process. The membrane reactor was used for solid-liquid separation and slurry concentration. After recovery and reconstruction, the system is stable, smooth flow, reliable, safe and convenience. The production capacity is 0.74-0.8 m³/h and achieves the requirement of the system. The low-level radioactive waste water removal efficiencies for total α and β are 99.65% and 98.20% respectively. Low-level radioactive waste water can be discharged.