The emotions of students are more and more important in learning. Positive emotion can help not only learning but also solving problems. In previous research, most of them emphasize on the feedback by virtual agent instead of self-awareness by students. The purpose of this study based on affective computing is to know if the learning system with avatar can improve the learning motivation, we build a system with an avatar that represents students to let them know the exactly emotion of themselves. The findings reveal that the system can affect the emotion of student, and improve the learning motivation.