The occurrence of uveal and cutaneous malignant melanoma and the dysplastic nevus syndrome in the same individual suggests an etiologic relationship among these diseases. Thus, the dysplastic nevus syndrome could be viewed as marking an increased risk of both cutaneous and ocular melanoma. We postulated that if such a relationship exists, patients with both forms of melanoma should have a high prevalence of dysplastic nevi. We examined 44 patients (31 women and 13 men ranging in age from 20 to 80 years) with uveal melanoma for evidence of cutaneous melanoma and dysplastic nevi. We also examined photographs of 46 patients (24 men and 22 women ranging in age from 19 to 67 years) with nonfamilial cutaneous melanoma to determine the prevalence of dysplastic nevi. We found a 4.5% prevalence of dysplastic nevi in patients with uveal melanoma, significantly lower than the 41% prevalence in patients with cutaneous melanoma (two of 44 patients vs 19 of 46 patients). This study indicates that uveal and cutaneous melanoma are not etiologically linked through dysplastic nevi and suggests that patients with uveal melanoma are no more likely to have cutaneous dysplastic nevi than the general population.