Abstract: According to the layout of cooling system in the medium/thick plate plant of ShouSteel and analyzing its heat transfer characteristics, the effects of different laminar cooling patterns on the temperature field of plate were investigated by the numerical simulation using finite difference method. The simulation results showed that the temperature difference between plate's interior and exterior increases with cool-down rate. To achieve the same final cooling temperature at constant cool-down rate, different laminar cooling patterns play important roles in the cool-down rate along plate gauge and temperature distribution. And it was shown that opening the spray header intermittent and thining out the cooling water spray are the best way to keep the cool-down rate constant without increasing temperature difference between the interior and exterior of plate.