In this report, the authors present a 14-year-old male patient admitted with progressive paraparesis and urinary incontinence that developed in a 3-month period. Thoracolumbar MRI revealed an intramedullary lesion starting from the level of the T10 vertebra and extending to fill the sacral spinal canal. Based on the radiological findings an intramedullary tumor was suspected. Exploratory operation with right L5 hemilaminectomy was done and the intraoperative finding was syringomyelia which was punctured with releasing of the tethered cord. The patient was followed for 3 years with clinical and radiological regression of the pathology and no symptoms and sings have remained. Syringomyelia can mimic intramedullary tumors clinically and radiologically. That is why it is useful to consider exploratory hemilaminectomy to confirm diagnosis.