In order to enhance the interaction between robots and humans, the human-computer interaction is more intelligent and natural. A facial expression recognition method based on channel attention mechanism is proposed. Using the biped humanoid robot NAO as an experimental platform, a human-computer interaction system capable of facial expression recognition is designed. First, the facial expression recognition algorithm of the attention mechanism is trained through the RAF-DB data set. The training results show that the model can recognize 7 basic expressions (happy, angry, nauseous, fear, sad, surprised and natural). Its accuracy rate can reach 76.7%. Secondly, design the voice and actions of the NAO robot when facing different expressions, and finally, test the entire human-computer interaction system. The test results show that when the NAO robot receives the emotions recognized by the computer, it will speak and act like a human.