Dielectric properties of yttria-stabilised zirconia (YSZ) alloys of nominal concentrations 9.5, 12, 15, and 18 mole% Y2O3 were measured over a temperature range from room temperature to 175 degrees C and a frequency range from 15 to 10(5) Hz. The dielectric properties of yttria-stabilised zirconia alloys decrease with increasing yttria content within the cubic region. Dipolar and conductivity relaxations occur concurrently in yttria-stabilised zirconia alloys with conductivity relaxation as the dominant part at lower temperatures. Using a simple approximation theory, a dipolar relaxation peak is claimed to appear at lower temperatures and frequencies.