<p>Against the backdrop of rapidly advancing digital economies, digital finance serves as a pivotal enabler for deep integration between digital technologies and the real economy, critical to advancing the green and low-carbon transformation of national energy systems. Utilizing panel data from 30 Chinese provinces(2011–2023), this study measures regional energy and environmental efficiency as the dependent variable using the non-radial directional distance function(NDDF). A two-way fixed-effects model is used to empirically examine the impact of digital finance development on energy and environmental efficiency and its underlying mechanisms. Empirical findings reveal that digital finance significantly enhances regional energy and environmental efficiency in China, with findings robust to multiple robustness tests. Heterogeneity analysis indicates that digital finance positive effect on energy and environmental efficiecy is more pronounced in regions with advanced green finance frameworks and economically developed eastern areas. Mechanism tests confirm that attracting Foreign Direct Investment (FDI) and strengthening regional technological innovation capabilities are critical pathways for digital finance to improve energy and environmental efficiency. Thus, digital finance emerges as an effective force in advancing China’s sustainable energy transition. To maximize the digital finance’s environmental benefits, policymakers should prioritize bridging regional development gaps, refining FDI-specific policy incentives, accelerating the construction of coordinated digital finance-green finance frameworks in central and western regions, and deepening the integration of digital finance with technological innovation.</p>