The theme of the 3rd international Symposium on Human Settlements Science in Mountainous Regions focuses on the security and sustainable development of human settlements science in mountainous regions. It mainly involves four topics: enriched tripartite theory of ‘city-architecture-landscape’ in contemporary mountainous regions, resource utilization and development protection of mountainous regions, disaster prevention and reduction and engineering technology for human settlements in mountainous regions, and historical, human and social approach to human settlements research in mountainous regions. It has broadened the width and depth of research on sustainable development of human settlements.