Urban Underground Space (UUS) development plays a crucial role in urban structure optimisation and resilience enhancement. As UUS is inherently sensitive and irreversible, scientific geological evaluations are essential to inform UUS planning and sustainable development. However, challenges such as the absence of unified evaluation criteria and insufficient integration of geological conditions into urban planning exist. To address these issues within Beijing’s urban context, we developed the standard for geological evaluation on UUS resources in the Beijing Plain. This standard defines a systematic evaluation procedure, an index system that incorporates both engineering geological and hydrogeological indicators, index grading and quantification, classification of overall evaluation levels, and evaluation scales that align with the varying requirements of UUS planning. As the first standard of its kind in Beijing, it enhances the consistency and practical applicability of geological evaluations for UUS, offering significant implications for sustainable urban planning and serving as a model for other urban areas.