The present study challenges traditional conviction that the philosophy of constitutionalism is endemic in western cradle by suggesting that there are constitutionalist ideas in Chinese classical Confucianism. The paper systematically generalizes the classical intellectual foundations of Confucian constitutionalism by taking the doctrine of rectification of names (zheng ming) as the pivot. My generalisation is as follows. Like any other form of constitutionalism, Confucian constitutionalism is generated due to the apprehensiveness of despotic government. In searching for an antidote to despotic government, the classical Confucians suggest a zheng ming government which can be understood as constitutional government. The purpose of this government is to ensure governmental responsibility for people’s welfare, which is well demonstrated in the concept of minben (people as basis). The Confucians then propose the means to articulate the standards for rectifying the governmental power, named as li – a variant of unwritten constitution. To enforce the li, they anticipate the practice of moral self-rectification by the ruler and the external rectification of ruler by wise and virtuous scholars. The study is concluded with a summary of the main findings and some reflections on the relation of Confucianism to the promotion of constitutionalism in contemporary East Asia.