Abstract: The concept of “harmony between nature and man” is an important category of Chinese philosophy and the ideological essence of Chinese excellent traditional culture. The unity of heaven and man embodies the unity of life view and universe view, the unity of natural law and moral law, and the unity of modern idea and historical thinking. Green development, community with a shared future for mankind, thought on development with Chinese characteristics embodied in Xi jinping’s ecological civilization thought, are the organic unity of ancient thought of “Unity of Nature and Man” with the thought of pursuing value rationality and instrument rationality in the new era, a new exposition of social development in the new.