Abstract The thermal and mechanical properties of cerium dioxide (CeO 2 ) were assessed using a range of experimental techniques. The oxygen potential of CeO 2 was measured by the thermogravimetric technique, and a numerical fit for the oxygen potential of CeO 2 is derived based on defect chemistry. Mechanical properties of CeO 2 were obtained using sound velocity measurement, resonant ultrasound spectroscopy and nanoindentation. The obtained mechanical properties of CeO 2 are then used to evaluate the Debye temperature and Grüneisen constant. The heat capacity and thermal conductivity of CeO 2 were also calculated using the Debye temperature and the Grüneisen constant. Finally, the thermal conductivity was calculated based upon laser flash analysis measurements performed on pellets fabricated using a range of feedstock purities to resolve discrepancies in the existing literature.