Dermal melanocytosis such as nevus of Ota and extensive Mongolian spots are sometimes associated with hemangiomatous changes. Ota gave the designation of phakorriatosis pigmentovascularis to a spectrum of these combinations. We oLserved four cases of phakomatosis pigmentovascularis. They showed extensive, various dermal melanocytosis and widespread nevus flammeus. They exhibited signs of involvement of the systemic organs such as abnormality of electroencephalograrn, soft tissue hypertrophy and convulsion.