Abstract: Biodosimetry has the advantages that can not be completely replaced by physical dosimetry. Its significance and scientific sense has aroused more attention of the radiobiologists in all over the world. It was showed that optimizing and correcting use of biodosimetry in any situa-tion should be set on the base of well understanding to what people used. The progression on the research and application of biodosimetry will be viewed and the criteria of practical biodosimetry will also be raised in the article.