In exploring the evolution of Iranian architecture from prototypes to the present day, Qajar architecture is an important part of Iranian architecture history. The importance of this era's architecture is because large changes in conceptual and physical context occurred slowly in Iranian architecture during this time. These changes, especially from the Nasserian period (the second Qajar era), have intensified and with the influence of Western architecture, Iranian architecture is gradually moving away from its traditional, rooted forms, manifestations and concepts, and blending European architectural patterns with Iranian models and styles to the extent that architecture progresses. These changes in Residential buildings (especially mansions) also appeared. Therefore, in this study, a comparison between the architecture of the residential buildings of the three periods of Qajar dynasties has been carried out to compare the changes of each period. The results showed that Qajar architecture has been influenced by western and European architecture from beginning to end.
