Subretinal neovascular membranes cause late visual loss and are important determinants of final visual acuity in patients with Vogt-Koyanagi-Harada syndrome. The purpose of this study was to determine the prevalence and risk factors associated with the development of subretinal neovascular membranes in Vogt-Koyanagi-Harada syndrome. We reviewed the charts of 58 patients (116 eyes) with Vogt-Koyanagi-Harada syndrome. We separated patients into two groups, one with and one without subretinal membranes. Demographic characteristics, namely age, gender, and race, initial and final visual acuities, duration and method of treatment, anterior chamber and vitreous cell, presence of fundus pigmentary disturbances, and phase of inflammation, were evaluated for each group. Overall, ten eyes (9%) of seven patients developed the subretinal neovascular membranes. Demographic characteristics among the two groups of patients were not markedly different (P > .10). Visual outcome of patients with subretinal membranes was significantly poorer than was that of patients without these membranes (P < .001). Eyes with subretinal membranes had a significantly greater degree of anterior chamber and vitreous inflammation (P < .02), greater incidence of fundus pigmentary disturbances (P < .02), and a greater frequency of chronic recurrent phase of inflammation, marked by recurrence of predominantly anterior chamber, and occasionally posterior segment, inflammation (P < .02). The membranes were located in the peripapillary (four eyes), subfoveal (three eyes), and macular extrafoveal (three eyes) regions.