A 28-year-old woman was admitted with a sudden loss of vision in the right eye. She underwent renal transplantation in June 1999 for chronic renal failure secondary to amyloidosis. Upon ophthalmologic examination, the patient was diagnosed with central retinal vein occlusion. Physical and laboratory examinations failed to disclose any remarkable pathology except for high homocysteine levels. Hyperhomocysteinemia has been reported as a potential risk factor requiring treatment and a significant association has been found between this condition and central retinal vein thrombosis.