In traditional rhetoric, personification is only a simple linguistic phenomenon. From the perspective of cognitive semantics theory, metaphor is regarded as a universal way of thinking and cognitive means. Metaphor is not only a linguistic phenomenon, but also human thought and ability. Personification metaphors emphasize the common ground between people and objects and describe objects as people. Personification metaphor is composed of the blending and mapping of meanings of various fields. Based on the theory of conceptual integration, this paper will reveal the phenomenon of personification and the process of its realization in modern Chinese. When we read a metaphorical article, the first thing that comes to mind is a mental space about the topic. Metaphorical processes also enable us to form another mental space. This is called the input space in conceptual integration theory. The work of capturing the commonality of information in the input space occurs in the generic space. The process of integrating selected elements in the input space is a work of the integration space. Personification imparts human characteristics to things. Unlike other kinds of metaphors, in personification metaphors, the entity of human can not be expressed. When there is no "person" in the input space, it can be supplemented by people's words, deeds, thoughts and emotions, and then the personification metaphor can be realized through metonymy. At this point, the metonymy process must exist. Conceptual integration theory reconstructs thinking and combination method when human beings use personification expression. Through conceptual integration theory, we can understand the cognitive process and thinking way of human beings more intuitively. Although there are various forms of language expression, the way of human thinking is regular.