The development of the Second Language Acquisition Theory is significance to the improvement on efficiency of English teaching. With the increasing development of globalization, the requirements of students’ English ability in China has also been increasing. Of all items, the improvement of oral expression is particularly urgent, not only for the demand of daily spoken communication, but also for some students to achieve specific speaking ability through standardized tests. Traditional teaching methods that attach importance to grammatical functions and language structures can not meet the students' scoring needs in English spoken test. Therefore, through the research on the second language acquisition mechanism, the problems and schemes of exam-oriented English spoken teaching have been improved, and the methods to enhance exam-oriented spoken English teaching have been summarized as follows. First, teachers should pay attention to students' emotional motivation and create an environment conducive spoken spoken learning in classrooms. Second, teachers should optimize the appropriateness of contents and the flexibility of presentation of language materials for students. Third, teachers should give students time to digest the knowledge explained in class.