In “Morphology of Folk Tales”, Propp attempts to present a clear definition of narration. In fact, Propp based his studies on apparent rules. This is why he referred to his work as “morphology”. For him, the word “morphology” means the definition of narrations based on their constituting units and the relation of these units to the whole narration. The starting point of Propp’s studies is his definition of narration: the transformation of a piece to another composed piece. The transformation of these pieces is called “event”. For him, an “event” is the basis of each narration. Therefore, Propp attempts to trace the basic events of each narration and to arrange them in a list. Moreover, he calls these fundamental events “function”. According to Propp, although the stories studied have different forms, yet they are of the same structure. “Function”, for him, is the simplest and smallest narrative unit. In other words, functions are like a chain in the story; characters’ actions and the different parts of the story are composed of all these elements as a whole. In this article, attempt has been made to deal with plot by an extract from “Hassanak-e-Vazir” from Taarikh-e- Beihaghi so that the writers of this essay find a suitable answer to the question: Why has the narrator in “Hassanak-e-Vazir” used different narrative voices. In order to answer this question, the writers will begin their research based on this theory: The narrator has used different narrative voices so as to enhance the reality of the work. In other words, because the language used in this narration is referential rather than emotional, there, it has a tendency to representation of signs rather than to the language itself).