Laser heating of a solid surface results in a temperature rise and thermal stress development in the region irradiated by a laser beam. The thermodynamic irreversibility associated with the temperature and stress fields can be quantified by entropy analysis. Consequently, in the present study, the closed form solutions for temperature and stress fields due to time exponentially varying laser pulse are presented, and the formulation of entropy generation due to temperature and stress fields is introduced. The simulation for entropy generation is carried out for steel substrate. It is found that entropy generation in the surface region of the substrate material is higher than at some depth below the surface, and entropy generation due to temperature field dominates over its counterpart corresponding to stress field in this region.