Gadolinium fitanate (GdxTiyOz,) and dysprosium titanate (DyxTiyOz) have been developed as burnable poison and neutron absorbing materials in nuclear application, respectively. They have high neutron absorption capability and unique neutron absorption efficiency. Since their thermal properties have not been well established as yet, their specific heat capacity and thermal diffusivity were measured and they were used to derive the thermal conductivity for the GdxTiyOz and DyxTiyOz with various compositions from room temperature to 1000 degrees C. We also investigated the effect of the sintering temperature on the thermal properties. Although they are chemically and physically similar, the trend of the thermal conductivity of GdxTiyOz and DyxTiyOz differed significantly. The measured thermal properties can be used for the safety and performance analysis which includes the precise temperature calculation for irradiation test and for the design for nuclear application. (C) 2006 Elsevier B.V. All rights reserved.