In this paper, a quantitative algorithm for direct and indirect energy savings is developed based on the database analysis of China's energy consumption per GDP in the last two decades. The result shows that direct energy savings due to improved energy conversion and end-use utilization efficiencies only account for 26.5% of the total energy savings, and that indirect energy savings due to increased added value of products, product shifts, and structure shifts in industries account for 73.5% of the total energy savings. Factors affecting indirect energy savings are then analyzed, and total energy system efficiencies and direct energy savings in 2020 are quantitatively estimated, which shows that enlarging indirect energy savings is a more crucial task for China's macroenergy conservation in the future. The paper suggests that China should pay more attention to indirect energy savings to improve the energy utilization output benefits by increasing the added value of products, optimizing product and industry structures, and improving production technologies. The potential of indirect energy savings in China is more significant compared with developed countries.