Al2O3/La2O3 composite ceramic,which La2O3 was introduced via liquid phase mixing,was prepared by a pressureless sin-tering method at 1 400 ℃ for 2 h.The effect of La2O3 addition on the microstructure and microwave dielectric properties of Al2O3/La2O3 composite ceramic was investigated.The results show that the cell parameters of the ceramic become larger due to the solid solution of La3+ into Al2O3 cell.LaAl11O18 was formed by the reaction of Al2O3 and La2O3 during the sintering,which was lo-cated among the...