Abstract: "Food Additives" is a professional skills course for food majors． Online teaching of "Food Additives" course was implemented through cloud classroom smart vocational education APP and Tencent classroom live broadcast． On basis of sorting out teaching objectives and content, online teaching was implemented, including course construction, pre-class preparation, in-class implementation, after-class arrangement, and teaching reflection． In process of online teaching, by carrying out rich, diverse and flexible activities, students' participation and learning effect have been effectively improved．