In the present study, entropy generation in an unsteady conduction-radiation heat transfer is studied numerically. The finite volume method is used to solve the governing energy equation comprising the radiative flux divergence. The entropy generation for the unsteady conduction-radiation heat transfer is a strong function of temperature and total heat flux (conductive and radiative) distribution, which vary significantly with optical thickness and wall emissivity. Entropy generation decreases with an increase in modified Fourier number (a non-dimensional time) and reaches a minimum at a steady state for the cases considered. Entropy variation is substantial near the walls and least towards the center of the medium.