Binocular visual function after surgery for detached retina was examined in 100 patients with a visual acuity of less than 0.3 in the reattached retina and with a visual acuity of more than 1.0 in the non-detached retina: 1) There was no significant sex difference in binocular visual function. 2) There was no significant difference in binocular visual function according to postoperative interval. 3) Maintenance of postoperative binocular visual function was best in patients under 19 years of age, and grew worse with age. 4) In patients with a visual acuity of more than 0.1 in the reattached retina, simultaneous perception was good in 100%, and fusion in more than 80%. However, stereopsis was worse in most cases. 5) In patients with a visual acuity of less than 0.1 in the reattached retina, all aspects of binocular visual function were worse, except in those under 19 years of age. 6) There was no significant difference in binocular visual function between patients with and without temporary amputation of extrinsic ocular muscles at operation. 7) There was no significant difference in binocular visual function between patients with and without macular detachment before operation. 8) In the patients who had had an encircling operation, binocular visual function was worse than in those operated on with other procedures, because the former had the severest retinal detachment.