Abstract:Human beings create politics with a purpose, but the political purposes of different countries in different eras are very different. Thus, there is a question of whether the political purposes are justified or not. Political purposes can be divided into fundamental and overarching purposes, as well as derivative and unitary purposes. The former can be regarded as the political ultimate purpose, or ultimate political purpose of politics. The question of rationality of the ultimate political purpose is a key concern of political philosophy, because the rationality of the ultimate political purpose is the fundamental premise and ultimate basis of whether a politics has its due value or whether it is beneficial or harmful. The ultimate political purposes of different countries in different eras in history are varied, and thinkers have provided various theoretical answers to this question. Comparative analysis shows that only the “comprehensive and free development of every individual” (which can be transformed into “comprehensive and free development of all people in society”) proposed by Marx is a truly rational ultimate political purpose. The rationality of this ultimate political purpose lies not only in its embodiment of the requirements of human nature, but also in its absorption of nutrients from various historical views on happiness,and thus it is comprehensive and transcendent. The ultimate political purpose can be regarded as the ultimate goal of political ideals, while political ideals are the planning or design of how to achieve the ultimate political purposes, and the two are essentially consistent. Only when reasonable political purposes are achieved can the nature of politics be truly realized, and politics can have its due value.