In order to establish development goals and identify development priorities, deepening the strategic layout for ecological civilization construction in China requires an international comparison of ecological civilization construction in China and abroad. This research establishes an indices system for the international comparison of ecological civilization construction; evaluates the Group of Twenty (G20) economies based on ecological condition, environmental quality, social development, and resources utilization; and ranks the G20 economies on an ecological civilization index 2017 and on an ecological civilization construction progress rate (1990—2015). The results show that China’s level of ecological civilization construction ranks far below those of developed economies, especially in terms of environmental quality and resources utilization. However, China's construction speed ranks first among the G20 economies. This research analyzes the task hierarchies, strategic emphases, and time nodes required for China to catch up with advanced levels of ecological civilization construction.