Abstract: Practical aesthetics puts forward the ontological property of “du”(“度”，measure or degree) based on human production-life (i.e.practice-practicality),where “du” is not ontology itself,but has some unique attribute of ontology,it “is the first category of the historical ontology of anthropology”.The so-called “ontology of ‘du’” fixes “measure”as an abstract metaphysical concept of origin,ignoring the relationship between “degree”and real practice.The concepts of“the ontology of ‘du’” and “the ontological of ‘du’” are confused.To solve this problem,we should clarify the core meaning characteristics of the ontology of “du”.