“Four exactness” is the basic quality of teachers who teach ideological and political theory and is also the fundamental premise to improve the teaching quality of this course. To understand the “four exactness”， it is necessary to identify the definitions of “understanding exactly” “believing exactly” “using exactly” and “being competent exactly” from the connotation and denotation. Therefore， in order to adhere to the “four exactness”， we need to unify the relationship between scientific research and teaching， teaching and education， thoughts and action. In general， according to the “four exactness”， the foundation is understanding exactly， the core is believing exactly， the key is using exactly and the guarantee is being competent exactly.