Abstract: China's vast stock of existing buildings poses significant challenges to safety risk management. Traditional manual inspections and structural health monitoring are limited by spatial coverage, high costs, and poor real-time capability, failing to meet the needs of citywide building safety oversight. To address these issues, this study proposes a wide-area building safety monitoring framework based on the “Space-Air-Ground” collaborative monitoring technology. By analyzing typical building safety incidents and reviewing current inspection standards, key safety parameters are identified from the dual perspectives of “Risk Source” and “Risk Exposure” within the theoretical framework of urban safety "Risk Source-Risk Exposure-Risk Mitigation". The space-air-ground collaborative monitoring technology serves as the core component of “Risk Mitigation”, forming a comprehensive technical system for large-scale building safety monitoring. A hierarchical assessment approach—wide-area screening, targeted verification, and precise diagnosis—is established to enable macro-level surveying and micro-level localization of safety risks. This framework not only provides a scalable solution for urban building condition assessment but also supports the development of a dynamic safety management system featuring routine monitoring, ongoing evaluation, and accurate control. It offers practical value for enhancing urban resilience and governance effectiveness.