The extruded board thin plastering external wall thermal insulation system is a structural system of the extruded board thin plastering external wall thermal insulation system, which takes extruded board as thermal insulation material, uses special external thermal insulation adhesive to paste the extruded board, and uses anchor pieces to fix it on the external surface of the wall, uses special plastering glue as protective layer, alkali-resistant glass fiber grid cloth as enhanced anti-crack layer, and uses elastic paint or brick as decorative layer. Extruded polystyrene foam board (XPS) system material has solved the problems of heat preservation, crack resistance, wind resistance and weather resistance. XPS board has dense surface layer and closed cell structure, low thermal conductivity of inner layer, and good thermal insulation performance. For the same building exterior wall, its thickness is smaller than other types of thermal insulation materials (except PU) such as rubber powder polystyrene particles and EPS, and it has good moisture resistance, and can still maintain good thermal insulation performance in wet environments such as roofs, basements and cold storages; It is suitable for buildings with special requirements for thermal insulation, and can also be used for buildings with exterior wall facing materials of brick or stone.