Lumbar spinal canal stenosis (LSS) is a common spinal disorder among older people. Some LSS patients say that their pain worsens when they lift heavy objects. The Valsalva maneuver is the optimal breathing pattern for producing maximal force. Herein, we present two cases of LSS where the movement of the cauda equina was observed during the Valsalva maneuver.Case Summary:Case 1: A 74-year-old female with a history of LSS presented to our Department of Urology with frequent urination. The patient was diagnosed as having uterine and bladder prolapse. Pelvic cine MRI scan was conducted for detailed evaluation. While the Valsalva maneuver was performed to diagnose pelvic organ prolapses, we observed movement of the cauda equina. Spine MRI and CT, performed one year before presentation, showed severe LSS due to degenerative spondylolisthesis.Case 2: A 73-year-old male underwent radical prostatectomy for prostate cancer. A follow-up cine MRI to confirm urethrorrhea showed the cauda equina moving during the Valsalva maneuver. Moderate LSS due to degenerative spondylolisthesis was retrospectively found on abdominal CT performed before prostatectomy.Conclusion: The findings of our report suggest that movement of the cauda equina during the Valsalva maneuver may be implicated in LSS.