Low-density fibrous ceramic components (e.g., aluminosilicates) are widely used as insulating materials in boilers and furnaces. In practical applications the impact of hard particles such as ash or clinker may result in serious damage. The high temperature erosive wear of fibrous aluminosilicate ceramics has been studied to verify whether the mechanisms of damage change with temperature. The effects of temperature on erosive wear were examined with a gas-blast erosion rig and silica sand particles. For a vacuum-shaped board not subjected to an ageing heat treatment, a significant increase of erosion rate with temperature was observed, caused by the embrittlement of the initially amorphous fibres by mullite formation, which occurs rapidly at above 990 o C. For materials previously aged for 1000 h at 1260 o C, no variation of erosion with temperature was observed between 20 and 1000 o C. It was concluded that erosion rates measured at room temperature for these materials can be used to predict erosion at temperatures up to ca. 1000 o C.