Background/Objectives: Weight-related quality of life (WRQOL) and generic health-related quality of life (HRQOL) have been identified as important patient-reported outcomes for obesity treatment and outcome research. This study evaluated patterns of WRQOL and HRQOL outcomes for adolescents at 24-months post-bariatric surgery relative to a nonsurgical comparator sample of youth with severe obesity, and examined potential weight-based (e.g., BMI, weight dissatisfaction) and psychosocial predictors and correlates of these outcomes. Subjects/Methods: Multi-site data from 139 adolescents undergoing bariatric surgery (Mage = 16.9; 79.9% female, 66.2% White; MBody Mass Index [BMI] = 51.5 kg/m2) and 83 comparators (Mage = 16.1; 81.9 % female, 54.2% White; MBMI = 46.9 kg/m2) were collected at pre-surgery/baseline, 6-, 12-, and 24-months post-surgery/baseline with high participation rates across time points (>85%). Self-reports with standardized measures of WRQOL/HRQOL as well as predictors/covariates (e.g., weight dissatisfaction, social support, peer victimization, family dysfunction, loss of control eating, self-worth, and internalizing symptoms) were obtained. Growth curve models using structural equation modeling examined WRQOL/HRQOL over time and linear regressions examined predictors and correlates of WRQOL/HRQOL outcomes. Results: Significant improvement in WRQOL and Physical HRQOL, particularly in the first postoperative year with a leveling off subsequently, was found for the surgical group relative to comparators, but with no significant Mental HRQOL change. At 24 months, the surgical group had significantly greater WRQOL/HRQOL across most subscales. Within the surgical group at 24 months, weight-based variables were significantly associated with WRQOL and Physical HRQOL, but not Mental HRQOL. Mental HRQOL was associated with greater internalizing symptoms and loss of control eating. Conclusions: For adolescents undergoing bariatric surgery, most clinically meaningful changes in WRQOL and Physical HRQOL occurred early postoperatively, with weight-based variables as the primary drivers of 24-month levels. In contrast, expectations for Mental HRQOL improvement following surgery should be tempered, with 24-month levels significantly associated with psychosocial rather than weight-based correlates.