Central retinal vein occlusion (CRVO) occurred in 3 of 15 maintenance hemodialysis patients over a two-week period. There have been no previous reports of this ophthalmologic catastrophe observed in the dialysis setting. Lupus nephritis, Henoch-Schönlein purpura and nephrosclerosis constituted the patients' major underlying diseases. Moderate hypertension was also present. Impaired vision of the left eye noted 24 to 36 hours following dialysis was the presenting symptom in all cases. Findings included decreased visual acuity, retinal vein engorgement, hemorrhage, and disc edema. All three patients subsequently lost the vision in their left eye (two received anticoagulation therapy). With the exception of hypertension, there were no known underlying predisposing conditions present. Although we are unable to offer a definite explanation for these unusual cases of CRVO, we feel a hypercoagulable state may have been responsible. Because our three cases occurred during a two-week period, some transient unidentified procoagulant factor associated with hemodialysis could have been present.