Although the concept of “political thought” constitutes one of the central notions in the works of Tabatabai and in his analysis of the history of political thought in Iran, a careful examination of his writings reveals that this concept is not employed in a single, static definition. Rather, it is used and referenced within a conceptual system and across multiple levels, acquiring diverse meanings and functions in relation to various components of his theoretical framework. This study, adopting an analytical-conceptual approach and focusing on a close reading of Tabatabai’s primary texts, aims to investigate the semantic structure of the conceptual system of political thought in his works and seeks to clarify the essence of this concept in connection with the overall architecture of his theoretical framework. The findings indicate that Tabatabai, on the one hand, employs the notion of political thought in a philosophically-centered and narrowly defined sense, aligned with political philosophy and rational practical wisdom; on the other hand, within a broader framework, he conceives it as an integrated system of reflection on power relations and the organization of political life. A semantic examination of this conceptual system demonstrates that the concept acquires distinct and differentiated meanings depending on its relation to the various layers of his theoretical apparatus. The diversity in the application and function of the concept of political thought in Tabatabai’s works results from its multiple roles within these different layers. This research thus provides the possibility of a more precise and nuanced understanding of the internal logic of Tabatabai’s works and of his method for theoretically structuring the history of political thought in Iran.