Abstract: The heat transfer and thermal stress model for copper-steel colling stave is established by ANSYS.The temperature and thermal stress distribution of the stave is analyzed when the slag skull is steady and after the slag skull drops off.The result shows that gas temperature is the main factor that affects stave temperature and slag skull thickness and heat load and stress distribution.In the steady condition,the maximum of temperature on the copper plate is 124 ℃ and the heat load is 81.1 kW/m².The distortion is smaller than copper stave.After the slag skull drops off,temperature and stress on the copper plate increase rapidly.The temperature and stress state trend to stability when slag-drop time is 5 minutes.The copper plate and steel plate are combined firmly each other in the slag-drop state.