Phonetic Examination is a professional degree course for public security audio-visual technology. Based on the teaching experience of the past two years, the author believes that the introduction of cases in teaching and the realization of all aspects casebased teaching from theory to practice is the key to keep the course advance with the times and achieve ideological and political integration. In this paper, starting from the characteristics of strong timeliness and professional course, the case-based teaching of Phonetic Examination has the advantages, which is narrowing the gap between the theory of practice, following the rule of law technology progress and raising ideological and political standing. Combined with the teaching experience of the teaching platform in the past two years, the specific implementation of case- based teaching in Phonetic Examination is introduced, and the teaching effect is good.