We report a case of lumbar spinal hematoma caused by balloon-occluded retrograde transvenous obliteration for gastric varices in a woman in her 60 s with liver cirrhosis due to non-alcoholic steatohepatitis. The patient presented to the emergency department with a chief complaint of sudden nausea and hematemesis. Endoscopic sclerotherapy was performed, followed by balloon-occluded retrograde transvenous obliteration for residual varices. During balloon-occluded retrograde transvenous obliteration, she complained of back pain and subsequently developed thigh pain. CT and MR scans revealed subdural hematoma and subarachnoid hemorrhage within the spinal canal at the thoracolumbar level. It is presumed that balloon-occluded retrograde transvenous obliteration altered blood flow in the paravertebral plexus, causing an intraspinal canal hemorrhage. To our knowledge, this study is the first to report a case of an iatrogenic spinal hematoma caused by balloon-occluded retrograde transvenous obliteration.