On the basis of the necessity introducing of online course construction in colleges and universities in China, the background of course construction in "Food Additives" was introduced so as to strengthen the education and guidance of food additives for college students majoring in food, fully stimulate their learning initiative, and make better allocation of high-quality teaching resources. The methods on how to carry out the online course construction of food additives for students majoring in food science and engineering were also described with the help of the network platform based on the Intelligent-tree operation service system. The online course construction was strengthened and the teachers' comprehensive teaching level was improved by combing the chapter framework layout, refining the online topic knowledge points, clarifying the allocation of teachers and students' responsibilities, enriching the teaching forms, setting reasonable evaluation methods, and improving students' online learning effect. The construction of online courses not only makes up for the lack of supervision and management in the process of online teaching, but also enables the reasonable allocation of high-quality teaching resources among different colleges and universities, fully mobilizes the students' subjective initiative, cultivates their divergent thinking and independent thinking ability, and improves the learning effect and comprehensive quality of professional courses.