Background: Posterior reversible encephalopathy syndrome (PRES) is characterized by a combination of clinical and radiological features. PRES presents with the rapid onset of neurological symptoms, such as headache, convulsion, altered consciousness and visual disturbance. If PRES is recognized and treated early, it has a good prognosis. We present a patient with PRES due to systemic lupus erythematosus (SLE) and hypertension. This report aims to provide information for the early diagnosis and prompt management of SLE-related PRES to maximize patient outcomes. Case presentation: A 24-year-old woman came to the emergency department with an acute severe headache and visual disturbance. Two years earlier, she was diagnosed with SLE and hypertension. She was fully awake with normal orientation. Her initial blood pressure was 170/100 mmHg. Her visual acuity was 1/∞ (light perception only). Brain T2-weighted magnetic resonance imaging showed multiple hyperintensity patches at the occipital lobe and cerebellum; these findings suggested a diagnosis of PRES. Due to SLE-related PRES, she was treated with intravenous methylprednisolone, and her blood pressure was monitored. Her blood pressure was maintained using a combination of oral antihypertensive drugs. She was also treated with intravenous phenytoin for seizure prophylaxis. Her symptoms resolved completely, and her visual acuity returned to normal after 2 days. She was discharged without any neurological sequelae. Conclusion: PRES is a clinical syndrome with specific imaging findings. The diagnosis of PRES requires thorough clinical and neuroimaging examinations. Identifying the underlying cause and delivering prompt treatment is important for achieving a better outcome and minimizing neurological sequelae or mortality in patients with PRES.