The Cooperative Principle by American linguist Grice is one of the major principles guiding people's communication. Observing the Cooperative Principle will be helpful for people to improve the flexibility and accuracy of language communication. The ultimate aim of spoken English teaching is to develop students' communicative competence. Therefore, it is significant to apply the Cooperative Principle to oral English teaching. This paper tries to prove the applicability of Cooperative Principle in spoken English teaching.