<p>Although China has proposed dual carbon targets, its carbon energy consumption still grow in 2022. Optimization of energy utilization is an aspect of improving the energy and economic structure. However, Green finance diverges from conventional financial means, investing funds in green development to improve energy efficiency. Therefore, it is necessary to investigate the transmission mechanism of green finance in driving energy efficiency improvement. Based on empirical analysis of data from 2006 to 2020, this study examines whether the influence of green finance will be transmitted to both the supply and demand sides in order to encourage energy efficiency, and reaches the following conclusions. First of all, due to factors such as economic development levels and infrastructure conditions, there is an uneven development in energy efficiency and green finance levels in China. Secondly, green finance does have a promoting effect on total factor energy efficiency, especially in the green finance reform pilot zone. Finally, industrial structure optimization serves as the supply side, and energy consumption decarbonization serves as the demand side. They are both intermediary mechanisms for green finance to improve energy efficiency.</p>