Slender shaft parts are very sensitive to thermal deformation,especially in the case of multi-position cladding,it is difficult to control its deformation. The effects of different cladding positions,cladding sequence and constraints on the deformation of the elongated shaft were compared. Finite element method and life-and-death element technology are adopted to analyze the relation of temperature field and deforming. The experiment data were compared with ANSYS simulation data to verify the correctness of ANSYS modeling,mesh division and the real validity of temperature field,stress field and deformation simulation. In the subsequent axial repair projects,the optimal cladding path with minimum deformation and stress concentration is firstly optimized by ANSYS numerical simulation,and then the cladding work is carried out. It improves the processing quality and reduces the cladding cost to a great extent.