We measured autofluorescence of the macula with fluorophotometry to evaluate age-related changes in human retinal pigment epithelium. Examined in this study were 35 aphakic eyes of 25 patients, ranging in age from 52 to 87 years, after uneventful intracapsular cataract extraction and 21 normal phakic eyes of 20 patients, ranging in age from 9 to 29 years. Autofluorescence at the macula of aphakic eyes increased in an age-dependent manner (r = 0.514; p less than 0.01) as follows: 15.0 ngEq/ml for the sixth decade (n = 1), 17.2 +/- 4.2 for the seventh decade (n = 11), 21.3 +/- 3.6 for the eighth decade (n = 16) and 24.6 +/- 2.7 for the ninth decade (n = 7). We believe that the autofluorescence originates mainly from lipofuscin in the retinal pigment epithelium, and that the autofluorescence enhanced with age reflects the accumulation of lipofuscin.