Abstract: Biotechnology and bioengineering were the two easily confused concept of biology, so characterizing the two words was aid to teaching and construction fields. The present paper analyzed the different expression of the two items. It comprehended the two items from two angles of field of science and construction of field, clarified their connotation and relation, and then analyzed the relation of biotechnology with the other items i.e. life science, molecular biology, synthetic biology, and biomedical engineering. Finally, it also discussed the connotation and relations of bioengineering and biomedical engineering.

Key words: biotechnology, bioengineering, biomedical engineering, aim of majoring culture, technique of DNA recombination