Abstract: The model showed by the topic was introduced including a difference expression and some models for heat transfer coefficient air/water cooling specific heat and heat conductivity. Applying the finite difference method to the simulation of cooling process, the temperature field along the thickness/width of plate was calculated, as well as the effect of intermittent cooling on the result of cooling control. Simulating results show that the re-reddening time and temperature gradient along thickness increase with plate thickness and the inner temperature of plate decrease evenly if cooling intermittently, with plate surface continuously cooled and re-reddended. The on-line applications revealed that the model can get high accuracy in calculation to meet actual requirements in production.