Problem statement: Under the influence of  Imam Reza (AS) holy shrine, the Waqf institution has played a serious role in the spatial organization of Mashhad in different periods, especially in the Safavid era, but this issue has been less studied due to the difficulty in representing the urban spatial organization of previous eras.
Research objective: The present study intends to explain the effects of the Waqf socio-economic institution on the spatial organization of the city by representing the urban spatial organization in the Safavid era and examining the endowments of Mashhad in this period.
Research method: First the map of Mashhad urban spatial organization in the Safavid era was drawn based on maps, documents, and historical books, and in the next step, by examining historical sources and endowment letters, 45 identifiable endowed properties were located in the map and finally the location of these endowed properties in the relationship with the urban spatial organization were analyzed.
Conclusion: The result shows that the most important endowment-based change of the city of Mashhad in the Safavid era is the construction of the main street called “Chaharbagh (Khyaban)”, “Atiq Square” and two gates of Bala Khyaban and Paeen Khyaban. Urban spatial organization, including urban spaces, the arterial network of the main city, centers of activity, urban landscape and landmarks, natural organs, socio-cultural structure, and political-security structure, has been seriously transformed by endowment-based changes. Endowment-base changes while maintaining the organic connection with the old structure, changing the north-south structure of the city to the east-west direction structure. It organizes the centers of activity and the key elements of the urban and metropolitan scale, such as educational, religious, Sanitary, accommodational, and commercial land uses (which have been mainly endowed) in this axis. This has facilitated access to the holy shrine to the two gates and Arg-e shahi, making the two unique visual corridors and creating four significant landmarks.