This article disclosed the formation and evolution of acupuncture concepts, trying to find a new way to understand the inner meaning of these terminologies from the cultural perspective, such as the formation and evolution of “cunkou” in “Nei Jing”. Ideological origins should be contemplated in order to achieve profound and comprehensive understanding of acupuncture concepts. Literature research methods are the main method of this article. “Mouth” which is “kou” in Chinese is on behalf of one person's speech, a very important body organ to communicate with the world. “Mouth” was chosen to format the concept of “cunkou” to express the importance of pulse diagnosis such as “Duqu cunkou”.