Abstract: With the rapid development of my country's economy, the speed of energy development is gradually decreasing, and the problem of energy shortage has severely restricted my country's economic development. At present, "energy saving and emission reduction" is the basic national policy for the development of my country's energy industry. As the construction industry is an industry with high energy consumption, how to construct green buildings and energy-saving buildings has become the focus of attention in recent years. Building energy efficiency involves the entire construction phase, covering a certain structural part, such as doors and windows, walls, etc. Therefore, it is of great practical significance to carry out research on the technology of exterior thermal insulation and energy-saving renovation of building exterior walls. Based on specific cases, this paper analyzes the current situation of exterior thermal insulation renovation of building exterior walls, and on this basis, proposes a renovation plan, with a view to promoting the rapid and stable development of exterior thermal insulation technology of building exterior walls in my country.