Abstract: Biological dose assessment is an important means on radiation accident and occupational epidemic investigation. Cytogenetic bio-dosimeter has been very matured and widely applied through half century development. In order to reply to radiation emergency better, it becomes hot point of research to search new type molecular bio-dosimeters which are provided with quick and simple operation as well as fit in with application of great range crowd. The biological indicators of molecular level which have development potential of radiation bio-dosimeter are reviewed.