The invention discloses a high-performance thermal-insulation mortar, and belongs to the technical field of external wall thermal-insulation mortar. The high-performance thermal-insulation mortar is composed of, by mass, 25 to 40% of PO.42.5 cement, 50 to 70% of glass microbead, 0.5 to 2% of high-performance hollow ceramic microbead, 1 to 1.5% of polypropylene fiber, 2 to 4% of polymer latex powder, 0.2 to 0.4% of cellulose ether, 0.1 to 0.3% of a high-efficiency water reducing agent, 0.1 to 0.2% of an air entraining agent, 0.1 to 0.2% of organic silicon water repellent agent, and 1 to 1.5% of wood fiber. The high-performance thermal-insulation mortar is a single-component light dry mortar specially used for external wall thermal-insulation surface layers; combustion performance is capable of reaching A-class non-combustible; the high-performance thermal-insulation mortar is capable of preventing flame spread effectively, is a thermal-insulation material with excellent performance, is capable of protecting internal thermal-insulation layers from aging and deformation effectively, and prolonging service life of thermal-insulation systems.