The Sassanid Empire, on the one hand, claimed Zoroastrian religious heritage, and on the other hand, was in constant conflict with a powerful rival such as the Roman Empire over hegemony in the ancient world, so it follows a special model of the relationship between religion and politics. to respond to his conditions and needs. In order to investigate aspects of this issue, this article has raised its main question about the connection between religion and politics in the Sasanian era. The hypothesis of the article is that every pattern of power is related to a form of belief system that provides its explanatory and justification bases. The findings of the research have shown that the unity of religion and politics in the Sasanian era was one of the main bases of the discourse system of this empire, and many historical events of this period can be explained through this discourse basis. The method of the article is Foucaultian discourse analysis, and the data collection method was library and documentary.