<p>During China’s critical period of industrial structural transformation, the relationship between digital finance, industrial structure upgrading, and energy efficiency has become a crucial issue that urgently requires exploration in the process of economic growth. Based on annual panel data from 30 provinces in China from 2011 to 2022, this study constructs a mediation effect model to empirically examine the relationships among digital finance, industrial structure upgrading, and energy efficiency. The empirical results show that digital finance has altered the channels and operational efficiency of capital and energy utilization, directly enhancing energy efficiency. Meanwhile, it has also indirectly promoted energy efficiency by facilitating industrial structure upgrading. Further analysis reveals that the mediating effect of digital finance on energy efficiency is significant in the eastern region but not in the central and western regions. This study not only enriches the literature on the mechanisms through which digital finance impacts energy efficiency but also provides empirical evidence and policy insights for China to advance the development of digital finance, industrial structure upgrading, and energy transition.</p>