Background <p>This case is noteworthy as it presents an asymptomatic multisegmental epidural hematoma spanning five spinal segments (T12–L4) following unilateral biportal endoscopic (UBE) decompression, with the patient achieving favorable recovery without surgical intervention. This phenomenon has rarely been documented in existing literature and may serve as a reference for the management of epidural hematoma after UBE procedures.</p> Case presentation <p>An 82-year-old female patient (Chinese, the Han nationality) presenting with refractory left L5 radiculopathy and neurogenic claudication was diagnosed with degenerative lumbar spinal stenosis (DLSS) at L4–L5. Following unilateral biportal endoscopic (UBE) decompression surgery, postoperative computed tomography (CT) scans revealed extensive epidural hematomas spanning multiple spinal levels from T12 to L4. The epidural hematoma resolved with conservative treatment. At the 3-month postoperative assessment, the patient reported minimal lower limb pain and exhibited no bladder or bowel dysfunction. A follow-up magnetic resonance imaging (MRI) at 50&#xa0;days postoperatively confirmed complete resolution of the epidural hematoma. The development of multisegment intrathecal hematoma following UBE surgery is a rare complication with a complex etiology involving various contributing factors.</p> Conclusions <p>This case highlights critical considerations for UBE procedures: (1) multifactorial hematoma risks require meticulous surgical technique, staged rehabilitation, and thorough coagulation screening; (2) neurological deterioration mandates emergent MRI for surgical planning, while stable cases may respond to protocolized conservative care including monitored bed rest, osmotic agents, and coagulation correction. These findings underscore the need for risk-stratified postoperative management algorithms in endoscopic spine surgery.</p>