Background: The syndrome of transient headache and neurologic deficits with cerebrospinal fluid (CSF) lymphocytosis (HaNDL) is characterized by 1 or more episodes of severe headache, transient neurologic deficits, and lymphocytosis in the CSF. Case: A 15-year-old girl visited our emergency room for evaluation of severe headache for 14 days, right facial weakness, and right hemiplegia. The magnetic resonance imaging (MRI) with angiography and electroencephalogram (EEG) showed no remarkable abnormal finding. The opening pressure of lumbar puncture was elevated by 23cm H2O. CSF examination revealed lymphocytosis (cell count 31/µL, lymphocyte 64%) with normal levels of protein (57mg/dL) and glucose (35.5mg/dL). Virologic and microbiological tests of CSF were negative findings. After the medication of mannitol and dexamethasone, her headache and focal neurologic deficits were fully recovered. Two months later since the first episode, she re-admitted because of the headache, sudden dysarthria and numbness of left-sided tongue. MRI with angiography and EEG were rechecked and had normal results. CSF pressure was re-measured as 28cm H2O and CSF analysis showed lymphocytosis, and normal levels of protein and glucose. She discharged without neurologic sequalae in one week, and no relapse was noted in 6-month follow-up period. Conclusion: We recommend to check CSF examination for differential diagnosis in healthy adolescent presenting recurrent headache and concomitant neurologic deficit. When the diagnosis of HaNDL is correctly established, we can avoid invasive and expensive laboratory and imaging work-up.