With the rapid development of education digitization, artificial intelligence (AI) and knowledge graph, their application in the field of education has received extensive attention and research by many scholars. In this paper, the design of knowledge graphs for AI teaching platforms is studied. Based on the construction process of a general knowledge graph, teaching resources’ text is processed through the steps of knowledge entity recognition and relationship extraction, which is applied to the intelligent interactive teaching platform. On this basis, the article designs a method for teaching resource retrieval based on semantic analysis to provide a path for further teaching applications of knowledge graphs. After completing its design, application and testing are carried out to test its feasibility and effectiveness. The score of the experimental class that used the knowledge graph increased by 17.68, which is about 22.47% year-on-year compared to the pre-class period; the score of the control class also rose, with a rise of 9.41, which is about 11.53% year-on-year. The results indicate that a knowledge graph-equipped teaching platform can better meet the needs of interactive teaching and enhance students’ learning abilities.