Objective Degenerative lumbar disc herniation, hypertrophy of the ligamentum flavum, and nerve root canal stenosis caused by hyperplasia and coalescence of the synovial joints can be decompressed using laminar foraminoscopy on the herniated lumbar disc, synovial joints, and ligamentum flavum. Methods Twenty patients with lumbar disc herniation with lumbar degenerative radicular stenosis admitted to the hospital’s Department of Spine Surgery between 2013.9 and 2014.5 underwent lumbar foraminoscopic lumbar nucleus pulposus removal + enlarged nerve root canalplasty, and we performed VAS scores on the patients’ preoperative and postoperative lumbar and leg pain and Macnab scores on the results of the procedure. Results Intraoperatively, all patients were found to have nerve root canal stenosis on the symptomatic side of the operated segment. the mean preoperative VAS score for low back pain was 5 in 20 patients, 1.5 in the immediate postoperative period, and 0.5 at the 3-month postoperative follow-up. The mean leg pain VAS score was 7 preoperatively, 0.3 immediately postoperatively, and 0.1 at 3 months postoperatively. 18 patients were rated excellent and 2 patients were rated good for the efficacy of modified Macnab at 3 months postoperatively. Conclusion In patients with lumbar disc herniation with degenerative nerve root canal stenosis, foraminoscopy can decompress the herniated lumbar disc, the articular eminence joint, and the ligamentum flavum, effectively enlarging the nerve root canal and achieving excellent postoperative outcomes.