Abstract: In view of the problems of strong theory,complex formula,complicated mathematical deduction and difficult combination of theory and practice,this paper introduces a case teaching method in the classroom teaching of automatic control principle.In the classroom,the knowledge points are told through specific cases,from theory to practice and then to the theory,so that students can learn the knowledge taught by the teachers instead of accepting them passively.The practice shows that the case teaching method fully arouses the enthusiasm and initiative of students' learning,which is beneficial to students' understanding of theoretical knowledge,active classroom atmosphere,and promoting interaction between teachers and students.It has cultivated the students' innovative ability and the ability of linking theory with practice.It has improved the students' computer application level and achieved better teaching results.