It is difficult to let computer express feelings because of the ambiguity and nonlinearity. But it is important for people to communicate with computers and to built a society where people live with many robots. And it is said that expressing emotions is usuful for high quality data processing. In this paper, we construct an environment where an agent expresses its emotions to convey its intentions to other agents. First, we survey emotion models from the view point of psychology. Next, we propose an agent system that he can control other agents using his emotion expression as their communication method. Finally, we show that the agent could achieve his goal and that the agent had a kind of personality.