Paroxysmal homonymous hemianopsia (HH) is uncommon presentation of epilepsy. We demonstrate a rare case of paroxysmal HH that was diagnosed by magnetic resonance (MR) arterial spin-labeling (ASL). A 82-year-old woman presented with abrupt onset of isolated visual field abnormality without convulsive epilepsy at 16 days after a traumatic head injury. Diffusion weighted and MR-ASL obtained on admission revealed hyperintensity and hyperperfusion in the right temporo-occipital cortex. Nonconvulsive status epilepticus was suspected. The patient was treated with oral levetiracetam and the symptoms resolved in 3 days. Paroxysmal HH should be considered in patients who present with simple partial epilepsy, and MR-ASL imaging may assist in the differential diagnosis of these patients.