Abstract: By analyzing the one-dimensional heat transfer equation under the heat flux boundary condition, a numerical method for inverse computation from the back surface temperature data to the front surface reflectivity data is proposed. The inversely computing program is verified by the positive and inverse computation of one-dimensional heat transfer. The inverse computation results are compared with the reflectivity measured in the experiments, showing that the variation trend of two reflectivity curves are in good agreement. Thus the inverse computation is feasible in one-dimensional temperature field.