Variable definitions and descriptions.

Promoting sustainable growth in the energy sector is key to China’s high-quality development under socialist modernization. Based on dynamic capability theory and the resource-based view, this study uses unbalanced panel data (2011–2023) of Chinese listed energy enterprises to examine how digital transformation (DT) impacts sustainable development performance (SDP), including its subdimensions: financial performance, environmental‒social governance (ESG), and innovation. Using two-way fixed effects models and mediation analysis, we find that (1) DT significantly enhances SDP; (2) this improvement operates through alleviating financing constraints and optimizing resource allocation efficiency; and (3) the benefits are more pronounced in small-scale enterprises and downstream segments of the energy value chain. These findings deepen the understanding of the role of DTs in sustainable development and provide practical guidance for energy firms.