Golestan Palace is one of the architectural treasures of the Qajar Period in the Arg of Tehran. The inner section of this palace has been constructed based on a combination of Iranian and western architecture. The present study focuses on the changes in the architecture of the inner mansions of Golestan Palace in the course of history. Moreover, it examines the changes in the spatial and skeletal changes of this palace. Based on a descriptive-analytic study of some written sources such as newspapers, books, and memoirs as well as photos in the album house of the palace, the author has
tried to portray the historical process of the construction, destruction, and changes of the inner mansions of Golestan Palace. The findings of the study reveal the occurrence of massive changes in the internal structure of the place so that even the forms of ivans, stairways, and the columns have undergone some changes.