Purpose Achieving an adequate level of patient's satisfaction with results is one of the goals of adult spinal deformity (ASD) surgery. However, it is unclear whether the same factors affect satisfaction in all patient populations. Patients' age influences the postoperative course and prevalence of complications after ASD surgery. The purpose of this study was to determine the factors predicting satisfaction 2 years after ASD surgery in younger and older patients. Methods A total of 119 patients under 40 years old, 155 patients 40 to 65 years old, and 148 patients over 65 years old at surgery who were followed for a minimum of 2 years after surgery were included. Multivariate analysis was used to determine independent related factors with maximum AUC for satisfaction 2 years after surgery in each group. A propensity-matched cohort under equivalent demographic and clinical characteristics was used to confirm the results. Results Logistic regression analyses revealed satisfaction among the under-40 group corresponded to prior spine surgery, complications, and self-image. That among the 40-to-65 group corresponded to neurologic complication, revision surgery, pain, and sagittal vertical axis restoration. Among the over-65 group satisfaction correlated with revision surgery, standing ability, and lumbar lordosis index restoration. Propensity score matching confirmed that sagittal alignment correction led to substantial satisfaction. Conclusions In younger patients, avoiding complications and improving patients' self-image were essential for substantial satisfaction levels. In older patients, revision, standing ability, as well as sagittal spinopelvic alignment restoration, were the key factors. Surgeons should consider the differences in goals of each patient.