Oculodermal melanocytosis (ODM) is a developmental disorder of the embryonic neural crest involving virtually all of the structures of the eye derived from this tissue. The authors examined 194 previously unreported Thai patients with ODM. Elevated intraocular pressures (IOPs) developed in the ipsilateral eye of 15 patients at initial examination and in 5 others during follow-up, for a total of 10.3% of the patients. Three patients had congenital or late congenital glaucoma, 14 had ocular hypertension or open-angle glaucoma, and 3 had acute angle-closure glaucoma. Five of the patients with open angles had acute pressure rises accompanied by anterior uveitis. Melanocytic hyperpigmentation of the anterior chamber angle was extensive in all patients except those with acute angle-closure glaucoma. There was no consistent correlation between the extent or density of angle pigmentation and the development of elevated IOP. A larger cup-to-disc ratio in the involved eye, presumably congenital, was present in an additional 19 patients. Glaucoma is common in eyes with ODM and may develop at any age. Patients with ODM and initially normal IOP should be examined at regular intervals. Patients with open angles and acutely elevated IOP should be examined carefully for signs of anterior uveitis and treated medically.