Purpose: To report a case of recovery of bilateral cortical blindness in a patient with posterior reversible encephalopathy syndrome. Case summary: A 46-year-old female visited the ophthalmology department due to abrupt visual acuity decrease. Ten days earlier, she had received conservative management due to anemia caused by menorrhagia and uterine prolapse. She underwent a gynecological operation to remove a uterine myoma two days previously, and was given a blood transfusion postoperatively because of excessive bleeding. After the transfusion, she complained of acute blurred vision. Her best corrected visual acuity (BCVA) was hand motion 10 cm in both eyes. There were no abnormal specific findings except retinal dot hemorrhage at the temporal side in the left eye on fundus examination. Her pupillary light reflex was normal and optical coherence tomography examination was unremarkable in both eyes. However, flash visual evoked potential findings showed reduced P100 amplitude in both eyes and she was diagnosed with posterior reversible encephalopathy syndrome based on brain magnetic resonance imaging. After close observation without any treatment, the symptoms gradually improved. Finally, her BCVA recovered to 1.0 and P1 and P100 amplitudes were restored to normal range in both eyes at 16 weeks from the first diagnosis. Conclusions: A patient complained of bilateral visual loss without other neurological symptoms after chronic blood loss and blood transfusion. She recovered visual acuity completely with prompt diagnosis of posterior reversible encephalopathy syndrome and close observation only. J Korean Ophthalmol Soc 2016;57(9):1498-1505