Abstract: Aiming at the problem that the head vertical range of conventional vertical lathe is limited and it is difficult to meet the one-time clamping and turning of large workpiece, the structural design and engineering application of the super-long cutter row of large vertical lathe are completed. Three different cutter row cross-section structures, including solid, hollow and hollow reinforcement, are designed. The deformation, stress value and natural frequency are analyzed by the finite element software, and the structural performance of cutter row is further compared and verified by the engineering application. It can be obtained from the results that hollow reinforcement is the optimal cutter row cross-section structure type and its optimal cutting parameters are also determined. The turning problem of inner hole in a large-scale power generation equipment part as a single station state is solved.