We report a 7-year-old girl with Henoch-Schönlein purpura who developed hypertensive encephalopathy. She showed a sudden onset of neurological symptoms, including hypertension, convulsions, disturbance of consciousness, and cortical blindness. Reversible posterior leukoencephalopathy syndrome was diagnosed from the findings on magnetic resonance imaging. Reports of this syndrome in patients with Henoch-Schönlein purpura are very rare. However, if symptoms suggest central nervous system involvement, neuroimaging should be done for rapid diagnosis, and immediate treatment should be provided to avoid sequelae.