Abstract: As a late-developing modern country, one of the challenges that China is facing in order to achieve the Sustainable Development Goals (SDGs) by 2030 and build a beautiful China by the middle of the 21st century is to deal with the relationship between modernization and ecological transition. Unlike the ecological modernization transition initiated by developed capitalist countries, the modernization of harmony between humanity and nature embodies the distinctive Chinese characteristics of Chinese modernization and meets the essential requirements and green essentials of Chinese modernization. Guided by Xi Jinping's Thought on Ecological Civilization, the modernization of the harmony between humanity and nature is based on the scientific view of nature that "human and nature are a community of life", focused on the scientific strategy concept "to plan economic and social development from the height of harmony between humanity and nature", and settled in the dialectical development concept of "lucid waters and lush mountains are invaluable assets". The greatest theoretical and practical innovation significance of the modernization of harmony between humanity and nature is that it provides thinking for resolving the contradiction between modernization and ecological transition at three aspects, namely, the contradiction between ecological preservation and ecological development, public ecological interests and private economic interests, and the present generation and future generations. Foresight, dialectic thinking and people-orientation show the distinctive characteristics of the modernization of harmony between humanity and nature. The vivid practice of promoting the modernization of harmony between humanity and nature in China will provide Chinese wisdom and Chinese solutions for the realization of a new type of modernization, break the myth of "Modernization = Westernization" in solving global ecological crisis, and be of reference significance for many developing countries on the road of late-modernization.