beta-Si(6-z)Al(z)O(z)N(8-z)s(z = 1-3) have been synthesized by combustion synthesis (CS) and the as-received powders were densified by spark plasma sintering (SPS). The thermal properties of the dense beta-SiAIONs have been investigated by the laser-flash method from room temperature to a high temperature of 800 degrees C. The highest thermal conductivity of 9.45W m(-1) K-1 was obtained when z = 1 at room temperature. Both thermal diffusivity and thermal conductivity decreased with an increase in the z value. In the beta-Si6-zAlzON8-z, with z value increasing, more Si4+ and N3- ions get replaced by Al3+ and O2- ions, thereby more lattice defects are formed. These defects cause phonon scattering, accordingly reduce the thermal conductivity, (C) 2013 Elsevier B.V. All rights reserved.