Abstract: For thousands of years, the political legitimacy of the West has undergone multiple transformations from ancient Greece to modern times. The political legitimacy of the ancient city-state community of Plato and Aristotle lies in political justice, while the political legitimacy of the Middle Ages came from God, leading to the superiority of divine power over secular power and the political goal of obeying God. Since modern times, the advent of market economy has fundamentally changed the political demands of the world. The shift in political philosophy of Hobbes and Locke is deeply rooted in the rise of modern market economy in their economic life. The deep root of reconstructing politics or political legitimacy through contracts lies in the advent of modern market economy. Under the conditions of the capitalist system, the market mechanism of wage labor and capital exchange has a dual role. On the one hand, it frees people from the personal dependence relationship between individuals, achieving formal freedom and equality for all. On the other hand, it puts workers under the exploitation of the capitalist system as a whole, making it impossible to achieve true human freedom and equality. Habermas' theory of legitimacy crisis points out that even in late capitalist societies, class compromise has become a new social and political feature. However, due to the lack of possibility for deep structural changes, it is still in a crisis of legitimacy.