Due to the viscoelastic properties of bituminous concrete, temperature changes result in significant mechanical effects. This paper proposes a method to assess, first, the intrinsic thermophysical parameters (thermal conductivity and heat capacity) of a bituminous mix, and then to characterise its mechanical behaviour by performing complex modulus tests. The determination of thermal properties of bituminous mixtures comes from an inverse analysis using finite-element software. The obtained intrinsic thermal parameters are essential for the fatigue law that depends on the viscous energy dissipation of bituminous concrete.