Can Intercity Innovation Networks Promote Digital–Real Economy Integration? Evidence from 299 Cities in China

Deep integration between digital and real economic sectors (hereafter DREI) has become a salient engine underpinning high-quality and environmentally sustainable growth, yet comparatively little is known about how cross-city innovation networks shape this process. Drawing on a balanced panel covering 299 Chinese prefecture-level cities over 2006–2024, this paper examines whether and how a city’s eigenvector centrality in the intercity patent cooperation network affects DREI, drawing on two-way fixed-effects regressions, parallel mediation and moderation analyses, and a spatial Durbin framework. A city’s eigenvector centrality in the intercity patent cooperation network is significantly and positively associated with DREI, and this finding survives robustness checks and an instrumental-variable endogeneity treatment using lagged network centrality. Innovation network centrality is associated with higher DREI through knowledge spillover, resource allocation, and agglomeration economies, with the agglomeration channel being the strongest. Human capital, S&T investment, and digital governance positively moderate this effect, which is more pronounced in eastern, large, and high-policy-intensity cities. Furthermore, significant spatial spillovers exist and are stronger under provincial proximity than under geographical distance, varying across economic association patterns. These findings provide empirical evidence for optimizing intercity innovation networks and advancing regional coordinated development of DREI.