A new theoretical thermomechanical explanation of the uneven transverse temperature distribution,along the width for thin and wide hot rolled strip was proposed.In particular,starting from the irregular pressure and friction distribution which led to an uneven heat generation,a 2D mathematical model of calculating the transverse temperature distribution was presented.A physical explanation for this problem was given and the model was used as an essential basis to build a corresponding FEM simulation model,in which heat loss and generation were considered.Deformation and friction heat were described in details.For a clearer and more logical analysis,the heat generation problem was split into two parts:one for the strip centre,and one for the sides,in correspondence with the temperature peak points at 100mm from the strip edge.Finally,the result shows that how the new theoretical model can lead to the exact interpretation of the measured uneven temperature distribution. A new theoretical thermomechanical explanation of uneven grain temperature distribution, along the width for thin and wide hot rolled strip was proposed. In particular, starting from the irregular pressure and friction distribution which led to an uneven heat generation, a 2D mathematical model of calculating the transverse temperature distribution was presented. A physical explanation for this problem was given and the model was used as an essential basis to build a corresponding FEM simulation model, in which heat loss and generation were considered. Deformation and friction heat were described in details. For a clearer and more logical analysis, the heat generation problem was split into two parts: one for the strip center, and one for the sides, in correspondence with the temperature peak points at 100 mm from the strip edge. Finally, the result shows that how the new theoretical model can lead to the exact interpretation of the measured uneven temperature distribution.