Abstract: Facing the two themes of order reconstruction in the Southern Song Dynasty, Chen Liang got rid of the theory of separation of Tao and utensils under the metaphysical thinking of Neo Confucianism, realized that essence and phenomenon formed a dialectical and unified relationship through the practice of human subject, put forward the political philosophy of "Tao depends on human existence", and turned the pursuit of necessity to the exploration of human practical nature. Through reinterpretation of Mencius’ theory of life, Chen Liang connected the gap between desire and morality from the perspective of the same desire of the people. The realization of "benevolence" should be achieved through the main gymnastics, so as to establish its "public and private attached" principle of political legitimacy. In order to ensure the integration of social morality and people's desire in political practice, the monarch must "hand over the cultivation and use "the monarch's way and the teacher's way", so as to unify the morality and work in the public interest.