Aristotle's Politics is the most important political work of ancient Greek thinkers, which was written in 326 BC. On the basis of analyzing and comparing the political systems of more than 100 city-states, his book systematically tells what is the best country for citizens from the viewpoint that man is a natural political animal. The book has 8 volumes, 103 chapter, which can be divided into 4 parts according to the content. The first part, volume 1, 3, tells the basic theory of city-state and regime. It advocates that the polis is a supreme and extensive social group, pursuing the highest and greatest good cause. Human beings are natural political animals, consisting of families and villages. According to its purpose and the number of supreme sovereign executors, political power can be divided into two categories: authentic and abnormal. The former are monarchs, nobles and republics, while the latter are tyrants, oligarchs and civilians. The second part, the second volume, refutes the viewpoint of abolishing private property and family, and comments on various political systems at that time. The third part, Volumes 4, 5 and 6, narrates the concrete forms, causes of changes and preventive measures of the civilian, oligarchy and republic regime in reality, and points out that the republic regime with the middle class as the main body is the most stable regime. The fourth part, Volumes 7 and 8, discusses the problems of morality, population, territory, nationality and education in the ideal city-state. Politics is recognized as the pioneering work of western traditional politics. The system it established and a series of political views had a far-reaching impact on the development of western political thought.