The ISO 9698 standard specifies the method for the determination of tritium in water quality, which is tested using the liquid scintillation counting method. Tritium is a radioactive isotope widely used in environment monitoring, the nuclear energy industry and radiation protection. The standard describes in detail the experimental steps of the liquid scintillation counting method, the required equipment, the preparation of reagents, Sample Handling and Data analysis methods. Through this test method, the tritium content in water can be accurately determined and the radioactivity level of the water body can be assessed, thus safeguarding the environment safety and public health. ISO 9698 is suitable for water quality monitoring institutions, R & D institutions and nuclear energy related fields. It provides a scientific and reliable technical standard for the detection of tritium content.