Abstract: The width spread of workpiece will directly affect the final product specifications during the continuous rolling of the copper bar. What is worse,if the width spread is out of control,it will deteriorate the surface quality of the product,and aggravate the surface wear of the roll. According to the process parameters and equipment data of the copper bar production line,the finite element model of 5^# stand rolling process in SCR 3000 copper bar continuous rolling mill is established in this paper. The width spread of the workpiece an d the effects of different rolling processes are analyzed. The results show that with the increase of the distance from the width center plane,the relative width spread increases slowly at first,then increases rapidly. When the edge of the workpiece is not in contact with the roll,it no longer subject to the extrusion deformation of the roll,and the relative width spread decreases rapidly. The friction coefficient,back tension and roll gap have a great effect on the width spread,while the rolling speed and front tension almost have no influence on the width spread. According to the actual demand,a width spread formula is fitted based on the simulation results,and the influences of the friction coefficient and back tension on the width spread can be precisely estimated by this formula,which can be employed in production practice.