The effective use of Blended teaching lies in realizing the organic combination of online and offline.Based on the goal of efficient classroom teaching,this paper focuses on student-centered design of Blended teaching fusion point,including teaching content integration,teaching activities integration and teaching evaluation integration.The BOPPPS teaching model is used to design the online and offline classroom teaching of engineering economics,which adopts the methods of reversal class,group learning,topic discussion,participatory learning and in-class testing,etc.,do a good job of pre-class,in-class and after-class organic combination,increasing teacher-student interaction and improving classroom effect,efficiency and efficiency,so as to achieve mutually beneficial teaching.The idea of teaching design is applicable to Blended teaching of professional courses in colleges and universities,and provides reference for the blended teaching reform of college teachers.