The purpose of this paper is to investigate the relationship of tradition and modernity in the formation of qajar s architectural architecture in 1298 - 1344. the necessity of study also lies in the fact that in qajar period, the values and traditions dominating the society have faded to some extent, and the lack of proper understanding of the qajar state from these new historical conditions has led to a change in the society, and the most important of which has been the interaction of tradition and modernity in the society in particular in sociological dimensions. As far as this time, in connection with the principles of traditional architecture and within the structures of a traditional city, the architecture gradually lost its old forms and assumed a western appearance. in this paper , a descriptive - analytical method with data collection tools includes documentary studies and library sources and documents and documents available to the interaction of tradition, modernism in the context of architectural identity of this era. at the end, these developments in the architectural field have been studied and discoveries especially in sociological dimensions are considered in this regard.