The dielectric properties and the microstructures of LaAlO 3 ceramics with CuO additions (0.25-1 wt%) have been investigated. The sintered LaAlO 3 ceramics are characterized by X-ray diffraction spectra and scanning electron microscopy (SEM). The ceramic samples show that a dielectric constant (ε r ) of 19-22 and a Q x f value of 5000-48,000(at 9.7 GHz) can be obtained at low sintering temperatures of 1370-1460 o C. The temperature coefficient of resonant frequency varies from -50 to -80 ppm/ o C. At the level of 0.5 wt% and 1 wt% CuO additions, low Q x f value of the LaAlO 3 ceramics is owing to the formation of the second phase LaAl 1 1 O 1 8 . With CuO addition, an 100-200 o C reduction in sintering temperature can be achieved for the LaAlO 3 ceramics.