Empirical Analysis of Digital New-Quality Productive Forces Driving Sustainable Industrial Structural Upgrading in China

In response to global sustainability challenges, this study investigates how Digital New-Quality Productive Forces (DNQPF), which integrate digitalization with green innovation, contribute to Sustainable Industrial Structural Upgrading (SISU) in China. Using panel data from 30 provinces spanning 2011–2023, a multidimensional DNQPF index was constructed, and a comprehensive econometric framework was applied, including two-way fixed effects, mediation and moderation analyses, Hansen threshold models, and Spatial Durbin models. The results indicate that DNQPF significantly enhances SISU (β = 0.291, p < 0.01), with household consumption upgrading serving as the key mediating channel. Regional heterogeneity is evident: Eastern provinces show strong effects (β = 0.295, p < 0.01) and central provinces exhibit catch-up potential (β = 0.467, p < 0.10), while the Western and Northeastern regions display insignificant effects due to digital infrastructure disparities. The threshold effects reveal diminishing returns beyond a DNQPF level of 0.239 (coefficient decline from 0.518 to 0.323, p < 0.01), a marketization level of 6.181, and an innovation level of 9.520. Spatial analysis further confirms positive spillovers (direct effects = 0.282–0.320; indirect effects = 0.260–1.317; p < 0.05). These findings enrich endogenous growth theory by integrating digital and green development into emerging economies and underscore DNQPF’s role in advancing SDG 9 (Industry, Innovation, and Infrastructure) and SDG 12 (Responsible Consumption and Production). Coordinated digital–green strategies, institutional reforms, and inclusive infrastructure are therefore critical for achieving sustainable industrial transformation in China and beyond.