The urban–rural relationships in China are experiencing a dual structure period, balancing an urban–rural development period and coordinated urban–rural development period, and urban–rural integrated development has become the current strategy. Urban–rural integrated development has become an important measure to address the unbalanced development between urban and rural areas. Despite proactive explorations by governments at various levels to promote integrated urban–rural development, the anticipated outcomes remain difficult to achieve due to multiple constraints, such as inefficient flow of production factors and unequal provision of basic public services between urban and rural areas. There is an urgent need to re-examine how to advance deeper urban–rural integration from the perspective of collaborative governance. Taking the Yangtze River Delta region as a case study, this research reviews related policy documents, official texts, and development plans regarding urban–rural integrated development, social (urban–rural community) collaborative governance, and urban development at the central and regional levels in recent years. Meanwhile, this study interviews experts in the field of public administration and government officials, and visits the experimental area and demonstration area of integrated development in the Yangtze River Delta region. Through grounded theory method and multi-level coding, concepts, initial categories, main categories are clear, and six core categories in total are identified: policy planning capability, public participation, participation of non-governmental organization, openness of government information, supervision and evaluation, and implementation capacity. This bottom-up construction of the theoretical framework serves as an extension and enrichment of collaborative governance theory. Based on the six core elements identified through the research, the Yangtze River Delta region may implement targeted policy adjustments across these dimensions to enhance the effectiveness of collaborative governance, and it may provide referential insights for urban–rural development practices in other regions.

The pronounced urban–rural dualistic structure in China has given rise to the imperative for urban–rural integrated development. Coordinating urban and rural development and promoting urban–rural integrated development are pivotal to China’s new-type urbanization, rural revitalization, and the advancement of common prosperity in the new era. Meanwhile, collaborative governance issues arising in the process of urban–rural integrated development have emerged as a significant research perspective. This study takes the Yangtze River Delta region as its research area and employs structural equation modeling to conduct an empirical investigation into the collaborative governance performance of urban–rural integrated development. Results implied that, public participation, participation of non-governmental organizations, policy-planning capacity, government information disclosure and policy implementation capacity, exert significant effects on collaborative governance performance; the hypothesized significant effect of monitoring and evaluation is not confirmed. Based on the empirical findings, this study analyzes the various influencing pathways and proposes corresponding policy recommendations for collaborative governance practices in urban–rural integrated development within the Yangtze River Delta region.