The paper considers the emerging concept of geosystem services (GS), highlights its importance for sustainable urbanization, and the use of urban underground space specifically. A theoretical framework to enable the incorporation of GS into urban planning has been suggested. GS complement ecosystem services (ES) by focusing on abiotic components and services of the environment. Clearly, sustainable urban development is one of the major challenges facing humanity today. In this study we explore how the concept of GS can help address the challenge of a sustainable urbanization via planning instruments. The paper reviews classifications of GS, planning approaches towards urban underground space, and experiences in inclusion of GS and ES in urban planning. Next, the paper elaborates a theoretical framework for the incorporation of GS in urban planning. The framework integrates knowledge on GS, man-made subsurface infrastructure, cultural assets, and traditional planning issues like land use, social and economic considerations. The paper further discusses various particularities, which urban planners may come across considering GS: (1) planning scales, (2) planning time frame, (3) GS inventory, (4) supply and demand for GS, (5) risks, vulnerabilities and disservices, (6) interplay between geosystem and infrastructure services, (7) planning documentation, (8) visualization and planning tools. Our research shows that the concept of GS has not yet been fully integrated into planning processes, despite the increasing need for its inclusion under the emerging development agenda of geothermal energy, hydrological and hydrogeological cycles management, and the rational use of urban underground space. The inclusion of GS into urban planning would constitute an important step forward to sustainable urbanization.