We evaluated long-term visual outcome in 28 patients (52 eyes) with retinopathy of prematurity after Xenon photocoagulation and/or cryocautery. The visual outcome was roughly classified into two groups: visual acuity of 0.6 or better and that of 0.2 or worse. The poor visual outcome resulted from macular degeneration, and risk factors for its development were small birth weight (Mann-Whitney's U test, p = 0.03), retinopathy plus disease (chi 2 test, p = 0.041), treatment of a large area of the fundus (Mann-Whitney's U test, p = 0.035) and the inside of the vascular arcade (Mann-Whitney's U test, p = 0.0034), and treatment by cryocautery (chi 2 test, p = 0.032). Macular degeneration occurred either as an isolated small focus extending circumferentially around the fovea or as a result of extension from the temporal degeneration caused by photocoagulation. These results suggest that intensive treatment for retinopathy of prematurity, in addition to the prematurity by itself, caused the development of macular degeneration. Overtreatment should be carefully avoided in retinopathy of prematurity complicated by disease in which photocoagulation needs to be done in the area posterior to the ridge.