We present a case with seizure, confusion, hypesthesia and paraplegia after intrathecal injection of fluorescein. A 41-year-old man was admitted to our institution for the management of the CSF leakage. Intrathecal injection of fluorescein was performed and he complained of severe pain and numbness in the lower extremities at the end of the injection. Four hours later, he exhibited confusion, paraparesis and two episodes of generalized seizures. Two days later, he showed paraplegia and all sensory modalities below the T12 level were absent. Spine magnetic resonance imaging revealed myelopathic change in the lower thoracic spinal cord. There was no improvement of weakness and sensory deficits in lower extremity even 14 days after fluorescein injection. We speculated that thoracic myelopathy was associated with the intrathecal injection of fluorescein. In spite of its rarity, the complication after intrathecal injection of fluorescein could be serious. Thus, obtaining an informed consent with discussion with patient before the procedure is mandatory.