Introduction  The paper aims to prove the reliable measures for water resources safety under the serious incident of inland nuclear power plant.

  Method  By comparing the treatment results of the radioactive waste liquid in inland nuclear power and the national standards, it analyzed the treatment measures for the radioactive waste liquid under the serious incident of inland nuclear power, meanwhile, put forward the measures in order to further improve the safety and reliability of nuclear station, which were strengthening standby power supply, increasing standby water source and increasing waste liquid storage tank.

  Result  The results show that under the serious incident, the radioactive material can be stored, blocked and treated in the plant by three radioactive material isolation measures of the containment holding, nuclear island plant retention and temporary storage in the pool at the plant.

  Conclusion  CAP1000 inland nuclear power has perfect incident prevention and mitigation measures, which can effectively eliminate the possibility of releasing a large number of radioactive materials by the design. The inland nuclear power has the ability to ensure the safety of water resources under the serious incident.