||This dissertation mainly focuses on Mou Zongsan’s moral metaphysics. The first chapter is devoted to the discussion on the problem of what Mou’s “moral metaphysics” really means. The discussion is carried out on the basis of the inter-connection among the three fundamental concepts, the principle of the transcendent reality, the human nature and the transcendent moral mind. For Mou Zongsan, these three categories are actually the same thing, and among them, the axial element is human nature. The second chapter discusses the role that Mou’s moral metaphysics plays in his interpretation of Kant. All the important concepts in Mou’s interpretation of Kant, such as intellectual intuition, thing-in-itself and the transcendent ego, originate from his moral metaphysics. That is the reason why there is some transformation in the meaning of these concepts in Mou’s works. However, from my point of view, this difference should be rooted in the difference between the horizon of Chinese philosophy and that of Kantian philosophy. The third chapter investigates the relationship between Mou and Heidegger. Mou criticizes Heidegger directly in his book and refuses to construct his metaphysics with such phenomenological method. Nevertheless, in the early works of Heidegger and also in Mou’s work, Kant is the central character and bears the most special significance. According to this, Kant’s philosophy can be regarded as the bridge between Mou and Heidegger. The last chapter uses the Heideggerian structure, being-in-the-world, as the cardinal structure of fundamental ontology to interpret Mou’s moral metaphysics. The concepts discussed in the second chapter, intellectual intuition, thing-in-it-self and the transcendent ego, also play a central role here. It is with regard to these essential concepts, and in view of Heidegger’s fundamental ontology, that Mou’s efforts in founding metaphysics could be better understood.