The “Sou Shen Ji” is a representative work of the Six Dynasties Zhiguai. It’s better than other novels in plots, narratives, or portrayals. Then the animal is the immortal themes of literature, and the way of people treat animals, will reflect the way that they think in their times. From the emblem of disasters to strange things, from the deity’s messengers to incarnation of monsters , there are one-third parts of “Sou Shen Ji” which about animals. How to induce the models of the texts? What’s the functions of animal roles in the texts? And they reflect some modes of people thought in their times. Therefore, this article is based on subject’s styles, and analyze their models. Second, to differentiate between subjects and objects on the animal roles, and make clear the their functions of texts. Third, to analyze the styles of thought, and propose the atmosphere of Six Dynasties. This article consisting of five chapters. The First Chapter is exordium, to explain the motive, the purpose, the scope, and the steps of this study. Then propose the definition of the ”Animal Writing”. The Second Chapter induce miscellaneous texts to become systematic theory depend on seven types of subjects. The Third Chapter discuss the functions of animal roles of “Sou Shen Ji”. First, to differentiate between subjects and objects on the animal roles depend on two concepts: ‘The role acts in the incident” or “The object which be described.” Second, to classify five types according the functions of animal roles, and expound the relationships between the functions and subjects. The Forth Chapter about the atmospheres of times. It combines with the Second and Third Chapters, to analyze people’s thought which displayed from “Sou Shen Ji”, and propose five styles to discuss with it. The Fifth Chapter is conclusion. First, to sum up the contents of this article. Second, to propose this article’s values and introspect for the defect of this article. Finally, to regard this article as an initial study, and hope to explain the contrast between the viewpoint of Six Dynasties and the viewpoint of today. And further in the future, to find the thought of us which be restricted unconsciously depend on the results of this article.