Our paper uses the ultra-efficient data envelopment analysis and Tobit model to evaluate the energy efficiency and regional differences of 30 provinces in China during 2006-2018. Based on this, the factors affecting energy efficiency in various regions of China are analyzed. The conclusions are as follows: From 2006 to 2018, China’s energy efficiency has generally improved, indicating that energy efficiency is getting more and more attention, but the efficiency level is still relatively low. There is still much room for improvement, and there is a gap between regions. Increase the difference. From the regional perspective, the areas with high energy efficiency from high to low are the eastern, central and western regions. Analysis of the factors affecting energy efficiency shows that industrial structure, marketization level, economic development level, foreign direct investment, technological progress and energy prices all have an impact on energy efficiency, but for different regions the degree of impact is different, and the energy in the eastern region Efficiency is most affected by technological progress and marketization. The main factor affecting energy efficiency in the central region is the energy price level, while the factors affecting energy efficiency in the western region are mainly the level of industrial structure.