Objective To investigate the effect of percutaneous endoscopic spinal decompression in patients with lumbar spinal stenosis. Methods A total of 90 patients with lumbar spinal stenosis from July 2021 to September 2023 were enrolled in the study. They were divided into two groups using a random number table method, with 45 patients in each group. The control group received conventional lumbar decompression surgery, while the observation group received percutaneous endoscopic spinal decompression surgery. The clinical efficacy, surgical indicators, pain scores, and Oswestry disability index （ODI） were compared between the two groups. Results After symptomatic treatment, the clinical efficacy of the two groups of patients improved significantly, and the observation group showed a higher effective rate than the control group （P<0.05）. The levels of surgical indicators （operation time and intraoperative blood loss volume） in the observation group were lower than those in the control group （P<0.05）, the hospital stay was shorter （P<0.05）, and the pain score and ODI values were lower （P<0.05）. Conclusion Percutaneous endoscopic spinal decompression has a significant effect on lumbar spinal stenosis, with significantly reduced pain levels and lighter lumbar dysfunction, which is beneficial for patient recovery. It can be used for reference and promotion in clinical practice.