This paper examines the role of Geospatial Information Systems (GIS) and Building Information Modeling (BIM), in improving the official land registration system in Iran. Official land registration, as a fundamental pillar of the legal and urban management system, faces a number of challenges such as imprecise property boundaries, lengthy processes, and the inability to represent buildings in three dimensions. GIS and BIM sciences and technologies, with their capabilities in accurate mapping, integration of spatial and attribute data, and intelligent three-dimensional (3D) modeling, can address these issues and enhance the accuracy, speed, and transparency of land registration. In particular, the integration of GIS and BIM in a 3D cadastral system enables more comprehensive management and precise representation of multi-unit and complex property ownership. However, significant barriers-including the lack of alignment between current registration laws and 3D data, absence of common data exchange standards between GIS and BIM, legal challenges in accepting 3D digital documents, shortage of skilled professionals, and organizational resistance-have limited the implementation of these sciences and technologies. This research, through a systematic review of scientific and legal sources, expert interviews, and analysis of international experiences, seeks to provide practical solutions for overcoming these barriers. Recommendations include amending registration laws to legally define 3D digital documents, developing national IranGeoBIM standards, delivering specialized training for experts, advancing Information Technology (IT) infrastructure, and leveraging new technologies such as blockchain for ownership storage and transfer. The results show that integrating GIS and BIM not only improves property registration but also offers significant applications in urban planning, contributing to sustainable urban development. The proposed roadmap includes short- to long-term steps for achieving a 3D GIS and BIM-based digital transformation in Iran’s cadaster and land registration system, which can increase efficiency, transparency, and legal security in this field.