Background: To examine the influence of obstructive sleep apnea (OSA) on the quality of life (QoL) in bariatric surgery. Methods: All patients who underwent a laparoscopic Roux-and-Y gastric bypass (LRYGB), preoperative poly(somno)graphy and completed an Impact of Weight on QoL-Lite questionnaire before and after surgery were included. Results: A total of 276 patients were included. OSA was diagnosed in 150 (53.3%) patients. All subscale scores improved 15 months post-surgery (p < 0.01). Total score improved from 51.2 (SD 19.1) to 89.7 (SD 13.9). Lower postoperative scores were seen in OSA patients on subscales Public Distress (90.4 SD 18.8 versus 95.7 SD 10.2; p = 0.003) and Work (92.9 SD 15 versus 96.1 SD 9.7; p = 0.031). All postoperative subscale scores were negatively correlated with OSA severity (p < 0.01). Conclusions: After LRYGB, QoL improved in both OSA and non-OSA patients. OSA patients, especially patients with severe OSA, have lower postoperative scores on subscales Public Distress and Work after LRYGB.