Introduction: Rare and benign, intramedullary spine dermoid swellings are primarily caused by the neural tube’s improper closure during development. They appear in the second and third periods of life and are slow-growing tumours. Only 1% of people have intramedullary dermoid cysts. Case report: We reported an 18-year-old female with backache which is mild to moderate intensity, gradually progressive and now increased to cause inability to lie down supine for 7 days. Patient also developed both lower limb weakness for 15 days which is gradually, progressive and now patient is bed bound for 5-6 days. Patient developed urinary retention 7 days back when she was catheterized at PVT Hospital. History of constipation present. No history of trauma / fever/ cough/loose motion. MRI Spine suggestive of contrast enhancing well defined intramedullary lesion at D12 level with cord expansion Patient underwent D12 laminectomy and symptoms improved postoperatively. Conclusion: It is uncommon for adults without a history of trauma to develop dermoid cysts. The therapeutic option is surgical excision. However, to keep an eye on the sensory-motor function, long-term monitoring is required.