With the more and more extensive and in-depth application of mathematics in economic research, the Mathematicalization of economic theory has been continuously strengthened, but at the same time, the criticism has never stopped. The fundamental reason lies in the ignorance of the changes of mathematics in economic research and the essential characteristics of economic theory and even scientific knowledge. The dialectical unity of structure and generation, certainty and uncertainty, finite and infinite describes the essential characteristics of economic phenomena and scientific knowledge, explains how mathematics constantly adapts to and promotes the development of economic theory, and further confirms the rationality of the Mathematicalization of economic theory and strengthens the scientific nature of economic theory.