To meet the lightweighting tendency of novel aerocrafts, ceramic insulating tiles with lower-density (0.25 to 0.30 g/cm³)were fabricated by adjusting densification degree, without changing the composition and primary processing parameters.The tiles' microstructure, thermal conductivity, mechanical properties and high-temperature insulation performance were analyzed.In addition, the effects of sintering temperature and the ratio of long fibers to short fibers on the tiles' thermal and mechanical properties were studied. The results show that the thermal conductivity decreases with decreasing density, while the mechanical properties and high-temperature insulation performance also decrease; increasing sintering temperature is an effective approach to improve the tiles' mechanical properties for lower-density tiles, while the different ratios of long fibers to short fibers do not affect the tiles' properties obviously.