Based on the seam-defect appearing on the plate edge of rough-rolling medium billet in the Meishan Iron and Steel Companys hot-rolling units, the five-pass reversible vertical-horizontal rolling of different vertical roll shapes process is simulated numerically. The results show that groove vertical rolls rolling can inhibit double bulging deformation better. On the same rolling process conditions, the value of side tumbling on groove vertical rolling is larger than that on flat vertical rolling, and the value of side tumbling increases with the groove fillet radius increasing. During the rolling process, that the metal at low temperature, high strain and high stress cumulates on the edge of the workpiece may bring the seam-defect along the length of the workpiece. The edge interlayers could be avoided by reasonably designing the vertical roll shape and optimizing the vertical rolls screw system, thereby reducing or avoiding the occurrence of seam-defects.