Established in integrated development, the construction concept and practice path of urban underground space are facing new opportunities, and the current mechanism of "combined civilian and combat" utilization still needs to be further improved and optimized. Based on urban underground space industry in the new era, the basic concept of the integrated development of urban underground space is systematically clarified, its evolutionary history and logical content are analyzed, and a quantitative assessment model of the potential for integrated development covering political and economic conditions, military and defense resources, underground rail transportation, and the use of urban underground space is established. According to publicly available relevant data, 12 typical cities in China are assessed and classified in terms of their potential for integration development. The study aims to promote the construction of an integrated developmentoriented underground space industry in the new era. The proposed assessment model can effectively aid the decisionmaking process of underground space development, and the application results also provide insights for the planning of underground space resources utilization in the cities concerned.