Far-out syndrome is a rare condition. To our knowledge, this is the first report of far-out syndrome in a hemiplegic patient. A 57-year-old woman was referred to our hospital with a 4-month history of pain extending from the right buttock to the lateral area below the knee. She had become left hemiplegic due to a cerebral hemorrhage 5 years before her first consultation at our hospital. Plain films showed right lateral osteophytes of the L5-S1 disk space, which had not been demonstrated on plain films taken 3 years before the onset of cerebral hemorrhage. On computed tomograms (CT) after radiculography, impingement of the right L5 spinal nerve was observed between lateral osteophytes of L5-S1 and the sacral ala. Since there was no response to conservative treatment for 5 months, resection of the sacral ala only was performed posteriorly via Wiltse's lateral approach. Just after surgery, complete pain relief was obtained. CT after radiculography would be an alternative imaging study for a patient with little evidence of impingement on other images. Although it remains speculation, these osteophytes may form from increased stress on one side versus the other in a hemiplegic patient.