57 children presenting with optic glioma, 30 of which with neurofibromatosis, were treated from 1956 to 1978 at the Institute Gustave-Roussy. In 3, the tumor was confined to a single optic nerve; 18 had a chiasm-infiltrating tumor and 36 a large tumor invading adjacent structures. At the time of diagnosis, all but 2 had visual deficit, 5 had endocrine dysfunction and 27 had symptoms of increased intracranial pressure. X-ray examinations showed an enlargement of the sella turcica in 28 out of 37 patients and enlarged optic canals in 39 out of 41 investigated cases. 25 patients were operated on (most often exploratory operation only) and all received a 50 to 60 grays irradiation. 42 patients are alive but 20 are blind and 26 present with important mental retardation.