This work investigates the temperature dependence of GaAs/AlAs thin‐film structures. Based on an ac calorimetric method, the thermal diffusivity of a 700 Å/700 Å GaAs/AlAs periodic structure is measured from 190 to 450 K. Thermal conductivity of the structure is derived from the experiment. The results demonstrate that the thermal conductivity/diffusivity of the structure are lower than its corresponding bulk values. The temperature dependence of its thermophysical properties is weaker than that of typical bulk III–V materials. Interface scattering is believed as the major cause of the observed reduction in thermal conductivity.