Study Design. A retrospective clinical study of patients who were treated from January 2011 to December 2018 and met our criteria. Objective. The aim of this study to investigate the relationship between radiographic spinopelvic parameters and the health-related quality of life (HRQOL) in pretreatment de novo degenerative lumbar scoliosis (DNDLS) patients with concomitant lumbar spinal stenosis (LSS). Summary of Background Data. DNDLS has garnered attention because of the increasing aged population. Unlike other types of spine deformities, DNDLS may occur with concomitant LSS. Radiographic spinopelvic parameters are important for evaluating spine alignment in these patients; however, the association between these parameters and the HRQOL is unknown. Methods. Data from 204 patients diagnosed with DNDLS and concomitant LSS were reviewed. HRQOL was assessed using the visual analog scale (VAS) scores (for the back and leg), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores, and Scoliosis Research Society (SRS)-22 questionnaire (SRS-22). Radiographic spinopelvic parameters were obtained from anteroposterior and lateral x-rays. The relationship between spinopelvic parameters and HRQOL was analyzed by correlation analysis in the overall population. Results. Lumbar lordosis (LL) showed clinical relevance to JOA (r = 0.290), ODI (r = -0.269), SRS-22 pain domain (r = 0.134), SRS-22 function domain (r = 0.257), and VAS for back pain (r = -0.196). There was clinical relevance between T1 pelvic angle (T1PA) and JOA (r = -0.212) and ODI (r = 0.251), sagittal vertical axis (SVA) and JOA (r = -0.211) and SRS-22 function domain (r = -0.229) and ODI (r = 0.215), and L1 pelvic angle (L1PA) and ODI (r = 0.200). HRQOL differences were validated in the SVA and PI-LL groups by SRS-Schwab classification. A significant difference was validated by setting a sagittal balance threshold for SVA, T1PA, T1 sagittal tilt, and L1PA. Conclusion. The sagittal radiographic parameters showed a weak correlation with preoperative HRQOL in patients with concomitant DNDLS and LSS. T1PA, T1ST, and L1PA can effectively assess pretreatment HRQOL.