Abstract: The communication of Xi Jinping's Thought on Ecological Civilization by mainstream media is the main means to deeply understand and promote his thought, strengthen ecological civilization education, and raise the awareness of ecological civilization in the whole society. This paper reviews the relevant content of mainstream media, and identifies the main characteristics of these mainstream media—focusing on major themes, construction achievements, and green stories. The basic strategies of communicating Xi Jinping's Thought on Ecological Civilization are summarized as follows: upholding the great banner of Xi Jinping's Thought on Ecological Civilization, adhering to the "people-centered" work orientation, grasping the new changes, new characteristics and new laws of the media environment, and expanding the global perspective to advance the international communication of Xi Jinping's Thought on Ecological Civilization. Finally, the paper proposes promotion paths for the communication of Xi Jinping's Thought on Ecological Civilization by mainstream media, which include enhancing the communication intensity and coverage breadth through the linkage of multiple subjects, triggering thought resonance and emotional resonance by telling good green stories, achieving three-dimensional presentation and efficient reach through innovative communication methods, and to demonstrating theoretical confidence and great power responsibility by strengthening international communication.