Objective:To determine the clinical outcomes of pedicle substraction osteotomy in revision adult deformity surgery and assess clinical benefit following revision adult spinal deformity surgery.Summary of Background Data:few study has analyzed the clinical outcome of PSO in revision adult spinal deformity surgery,and how to eveluate the occurrence of a major complication in PSO and the ultimate clinical outcome.Methods:Analysis of consecutive adult patients who underwent revision surgery by means of PSO for spinal deformity with a minimum 2-year follow-up was performed.All complications were classified as either major or minor.Outcome analysis was conducted with the Scoliosis Research Society(SRS)and Oswestry Disability Index (ODI)scores.Results:36 patients(mean age 38.8 years)were identified with a mean follow-up of 2.8 years(range 2-4).Primary diagnoses included idiopathic/de novo scoliosis(7),degenerative(5),trauma(8),neuromuscular scoliosis(4),congenital deformity(9),POTTs deformity(3),.Most common secondary diagnoses that necessitated revision surgery were fixed congital or sagittal imbalance and pseudarthrosis,Overall,21.5％of patients developed major complications (16.8%perioperative surgery-related (pedicle subtraction osteotomy);8.5%follow-up).Conclusion:pedicle substraction osteotomy in revision adult deformity surgery can achieve better congital and sagital correction with acceptable major complication