With the rapid development of artificial intelligence technology, Chatbot is also developing fast. The application of Chatbot in teaching can liberate the manpower required by relatively fixed and repetitive intensive tasks or processes in teaching. The customer-centered concept of Chatbot coincides with the student-centered concept of vocational education. This paper discusses the connotation of the teaching method of Chatbot. The project tries to combine the online evaluation OJ platform with Chatbot in order to energize the C language teaching and competition coaching. It analyzes the positive effects of Chatbot on C language teaching and teaching scenes, and actively explores the intelligent teaching mode based on AI.