A 42-year-old female end-stage renal disease (ESRD) patient with reversible posterior leukoencephalopathy syndrome (RPLS) post-transfusion during initiation of hemodialysis is reported. Eleven days after the onset of illness, we diagnosed encephalopathy as a grand mal seizure resulting from diffuse cerebral edema. One reason for the delayed diagnosis was that her symptom, a throbbing headache that occurred during her first dialysis, indicated dialysis disequilibrium syndrome. We must bear in mind that a small amount of transfusion could cause RPLS even during the first dialysis. To our knowledge, this is the first case report on RPLS after blood transfusion in an ESRD patient.