The developments between the Qajar and the first Pahlavi periods in Iran were accompanied by transformations in the political, economic, cultural, and social dimensions, which affected all aspects of the country's life at that time, including in the Tabriz. As a result, architecture and urban planning, especially the architecture of houses, underwent significant changes. political, economic, cultural, and social changes have had mutual effects on the architecture of houses, which has caused the house to become a place beyond the building; But less attention has been paid to the physical manifestation of these effects. This research aims to explain the mutual effects of social changes in Tabriz by analyzing the influence of factors such as the presence of the crown prince, strategic location and proximity to Russia and the Ottoman Empire, and their relationship with spatial changes in the architecture of houses. To achieve this objective, the research analyzes the physical, spatial, and functional alterations in the architecture of Tabriz houses and identifies the factors influencing these changes. This research was conducted using a qualitative approach, through field and library observations, the spatial patterns of 40 houses where it was possible to visit and collect documents, and it was done in a descriptive-interpretive way. The results indicate that changes and reforms in the architecture of the houses began in the mid-Qajar period. The reforms initially altered the lifestyle of the residents. Subsequently, especially during the Pahlavi period, spaces with Iranian identity, rooted in previous traditions and had various functions were either eliminated or changed in shape and nature and became single-functional spaces for sitting, sleeping and resting. a new form of the house was revealed by removing spaces such as inner courtyards, entrance steps (Rahrow, Dalan, and Hashti), Howzkhanehs, All-round Eyvans, Sarsaras and simplifying the form of the spaces.