Abstract: The thermal diffusivities of uranium dioxide containing various porosity aremeasured in temperature range of 573-2273K. Corresponding thermal conductivitiesare calculated based on the thermal conductive model. The correlation to fit thedata is obtained for the thermal conductivity of Uranium dioxide with temperatureand porosity as follows: K_p=1/4.42+20.3P+0.0197Te~(2.14p)+9.85×10~(-4)e~(-2.36p)T·e~(-1.12/K_B·T) The pore coefficients β and η in the Maxwell-Eucken's and Loeb's expressionfor porosity correction are derived. The results indicate the influence of porosityupon β is lower than η. We have <1173K β=1.99-0.44×10-~3T >1173K β=1. 64-0. 14×10~(-3)T The calculated Debye temperature of Uranium dioxide is agreeable to previousvalue obtained by other author.