In order to solve the problems of non-uniform axial deformation and thinning of wall thickness in traditional tube electromagnetic bulging, a method of tube electromagnetic bulging based on convex magnetic field shaper is proposed in this paper. The electromagnetic-structure coupling model is constructed by using COMSOL software, and the influence of convex magnetic field shaper structure on radial and axial electromagnetic force, axial deformation uniformity and wall thickness reduction is analyzed, and compared with traditional tube electromagnetic bulging. The results show that by using this method, the axial deformation uniformity is increased by 4.2 times, and the relative wall thickness is reduced by 33%. Obviously, this method of tube bulging can effectively overcome the problems existing in traditional tube electromagnetic bulging and promote the wide application of electromagnetic forming technology.