Aristotle's theory of virtue is one kind of social theory which suggests, individual practice of virtue is social practice and advanced practice of virtue can be possible when human society has developed some high level. The necessary and center part of eudaimonia is virtual practice, and eudaimonia is virtual life. Different practical activities cultivate different virtues and in some occupations, the tendency of their practices is such that the people in the careers can not get vitures. The best city-state shall be the whole citizenship who have all important virtues. However, it is one kind of ideal situation. We shall by justice value the real city-state. Justice is basic social virtue, and we can understand it by two ways, one is said that justice represents the whole virtue and entire interest of community, and the other is said that justice is part justice and ratio justice.