The opinion that poetry can express the feeling of discontent is a kind of literature theory which is firstly put forward by Confucious in the age of Chunqiu,People in that era employed poetry to express the discontent to politics, sentiment to life. Analysis reveals the discontent is not only the complaint to politics by people of insight, but also including the complaint to politics by common people and the bitterness and grief in lives of that era, which lay a foundation for the feature of sentiment in Chinese literature.