||In my research project, I am going to make clear the concept of Mr. Mou Zong-san's "Perfect teaching" in Buddhism. I want to show how he construct his model of "Perfect teaching" in Buddhism and study on his criteria of "Perfect teaching". Those are "Perfection in Prajñā" and "Perfection in Ontology". Moreover, Mr. Mou's "Perfect teaching" in Buddhism should be understood for his aim at explaining the problem "Sumum Bonum". The idea of "Sumum Bonum" urge him to form the "Perfect teaching" in Buddhism with being enlightened together with all the beings by the paradoxical way. Because of "Sumum Bonum", Mr. Mou excludes the Hua-yan School from the "Perfect teaching". I am going to reinterpret the text from Hua-yan School to argue that it should be a kind of "Perfect teaching" in Buddhism because it also can guarantee the unity of Buddha and the worlds of other sentient beings. At the same time, I shall discuss about the presuppositions that Mr. Mou holds and those only accept Tian-tai but refuse Hua-yan to be a "Perfect teaching" in Buddhism. Moreover, I shall argue that Mr. Mou's understanding of those paradoxical sentences in both Tian-tai School and the whole tradition of Buddhism is wrong since he "dissolve" those paradoxical sentences by treating them as ambiguous sentence. It is because the "Contemplation Tradition" of Tian-tai is ignored. In my opinion, the "Paradoxicality" in the sentences is the essence of those sentences and only made sense within the contemplation. I shall argue that the only way to treat the paradoxical sentences is to place them in the context of Buddhist "Contemplation".