During recent years quantitative evaluation has attracted a variety of concerns in the field of humanity and social science, including both reasonable introspection and unreasonable critics. In fact, quantity and quality are two sides of research achievement and one can’t be separated from the other. The qualitative evaluation must be based on quantity and the promotion of quality also comes from the accumulation of quantity. The two elements are integrated in the method of quantitative evaluation. This paper analyzes the relationship between quantity and quality, in the hope that people can have a dialectical attitude towards quantitative evaluation methods and can find a proper way to realize the innovation and reform of humanity and social science research evaluation.