Closure and growth of transverse cracks on slab surface severely affects the quality of rolled products. A finite element (FE)-based modeling on thermal and mechanical behavior of transverse cracks during hot rolling has been carried out using LS-DYNA software. The behavior has been simulated at a range of crack sizes, crack open-angles, friction factor between roll and slab. The maximum compressive and tensile stress at crack tip during rolling, the crack open-angle and the crack height after rolling, and the temperature on crack surface during rolling were analyzed. The mechanism of crack behavior during rolling is discussed.