Thoracic disk herniation comprises 0.15% of all disk herniation and has various and confusing manifestations. Among them, radicular pain down the leg could be the rarest presentation, especially if it is the only complaint. On the other hand, finding the relationship between clinical and paraclinical needs require high index of suspension and it is demanding. A 34-year-old patient, who had a history of intermittent back pain, with lower thoracic disk herniation presented by acute leg sciatica-like pain, is reported. He suffered 3 weeks of acute back pain prior to admission, which radiated down to buttock and leg, with a vague left abdominal pain, whose clinical examination indicated a distal lumbar problem. MRI showed T-12 L-1 disk herniation. Lower thoracic disc herniation can compress lumbosacral roots immediately after exiting from cord thickening in the lower thoracic area, so they can incite lower lumbar radiculopathy and cause discordance between MRI findings and clinical presentation, suggesting a lumbar problem, and this can lead to delayed diagnosis. However, the acute pain was completely improved after open discectomy.