This paper discovers that the divining events’distribution in the Shihchi is unbalanced both in the time and in the texts through the quantitative analysis of the divining events in the Shihichi. For the finding out the causes of these two unbalances , this paper doesn’t treat the writer’s understanding and thought about this field, but adopts the way of structure research. ,that is ,by inspecting and analyzing the role of the divining events’description in the Shihchi,and then we definite how much position they occupy in the structure, so that we can get the conclusion: most of the divining events play an important role in the structure of Shihchi.