Abstract: The study of the effects of ionizing radiation on the developing central nervous system and the underlying mechanisms is an important subject for the International Commission on Radiological Protection and United Nations Scientific Committee on the Effects of Atomic Radiation. Results from epidemiological investigations on A-bomb survivors are the main basis for evaluating radiation risk. However, given that these results reflect the biological effects of high-dose-rate single acute exposure, they cannot accurately reflect the biological effects of tritium beta particles under low-dose-rate continuous exposure. Radiation sensitivity of the central nervous system changes with its developmental stage, resulting in different radiation risks under various exposure situations. This paper reviews the achievements obtained in a series of comprehensive studies led by Dr. Zhou's research group of the former Laboratory of Industrial Hygiene, Ministry of Public Health (now National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention) from the 1980s to the present. Researchers used a total of 56 biological endpoints as evaluation indicators for physiological development, neurobehavior, brain pathology, and neurobiochemistry in prenatally exposed offspring, as well as electrophysiology, morphological, and biochemical changes in brain cells in primary cultures, comprehensively explored the effects and mechanisms of low-dose tritium β particles intrauterine irradiation on the developing central nervous system from multiple levels. This work is the first time to use the same experimental systems, from molecules, cells, and organs to the whole body, from tissue structure, neurobiochemistry, and behavior to learning and memory functions, to evaluate the risk of continuous low-dose tritium beta particle exposure on the developing central nervous system. These important achievements provide the most reliable and authoritative scientific basis for comprehensively and systematically evaluating the radiation risk of tritium beta particles on the developing central nervous system.