The resilience of urban agglomerations (UAs) is recognized because of their ability to withstand, adapt to, and recover from natural disasters and social threats. However, limited information on the resilience of specific urban agglomerations may hinder their sustainable development. The emerging concept of Social–Ecological–Technological system (SETS) resilience presents a novel framework for understanding and evaluating the resilience of UAs. Taking the Beijing–Tianjin–Hebei urban agglomeration (BTHUA) as a case study, we constructed a comprehensive resilience assessment framework. By incorporating the coupling coordination degree (CCD) model, modified gravity model, standard deviation ellipse, and obstacle degree model, we systematically evaluated the BTHUA’s SETS resilience. The results show that from 2010 to 2022, both the SETS resilience and its CCD in the BTHUA improved significantly. All the cities reached the coordination stage, with CCD values exceeding 0.6. The key cities enhanced their influence on the surrounding cities, resulting in a more robust and interconnected intercity resilience network. However, the BTHUA still confronts challenges in resource endowment, technological innovation, and public services, which warrant a more integrated and systematic approach to enhance regional SETS resilience.