Surface of a sample of a heterogeneous material and of samples with known thermal conductivity and thermal diffusivity is heated by a heating spot created by a heater and moving along the surfaces of all samples to determine thermal conductivity and thermal diffusivity of the heterogeneous material. Temperatures of heated surface of all samples are registered by three temperature sensors. Return of the heater and the sensors to the initial position is used for scanning with additional measurements of the sample thermal conductivity for a layer of the sample with depth and width different from those of a layer where thermal conductivity is measured during the forward direction.