BACKGROUND In neurofibromatosis type 1 (NF1) disease, the loss of the tumor suppressor function of the neurofibromin gene leads to proliferation of neural tumors. In children, the most frequently identified tumor is the optic pathway glioma. CASE REPORT We describe the case of a 5-year-old child who was diagnosed with NF1 and optic pathway tumor onset at the age of 14 months. Because of the tumor progression, chemotherapy with carboplatin and vincristine was prescribed at this early age and continued for one year. As the progression of disease continued after chemotherapy, the child, at the age of 2.8 years, was started on high-dose intravenous vitamin C (IVC) treatment (7-15 grams per week) for 30 months. After 30 months, the results of IVC treatments demonstrated reduction and stabilization of the tumors in the optic chiasm, hypothalamus, and left optic nerve according to radiographic imaging. The right-sided optic nerve mass seen before IVC treatment disappeared by the end of the treatment. CONCLUSIONS This case highlights the positive effects of treating NF1 glioma with IVC. Additional studies are necessary to evaluate the role of high-dose IVC in glioma treatment.