The application of the facial expression recognition system in the human-computer interaction system refers to the recognition of human facial expressions through the human-computer interaction system in the real society, so as to be able to feel the specific situation of recognizing people. This is also one of the main directions of human-computer interaction system research. In this paper, the facial expression recognition system is designed by the algorithm that combines the expressions of the students in the classroom teaching with the system environment, so that the recognition of the facial expressions of the students in the classroom environment is more accurate. This article elaborates on the identification method of the system, and conducts detailed experimental analysis on the specific functions of other modules in the system. The experimental results show that the security and stability of the system are very high. At the same time, the accuracy of the system in the classroom teaching environment is also very high in the recognition of student facial expressions. This is a modern intelligent face recognition system that enters education and teaching. Provide a strong theoretical basis and technical support during the work.