Abstract: According to the deformation characteristics of the steel pipe during the stretch-reducing process,the rolling process of the 21-stand stretch reducing mill is finite element analyzed (FEA) with the 3D model as set up via the ANSYS software.The analysis involves simulating the deformation course of the pipe being reduced,and a comparison of the pipe hexagonal ID occurrence trend and wall thickness variation resulting from the round pass parameter simulation to those resulting from the oval pass parameter simulation,which leads to the conclusion that in case of the oval pass parameter simulation,the occurrence trend of the hexagonal ID formation is smaller,and the wall thickness variation is also rather less.