Introduction: Massive retinal gliosis (MrG) is a rare, benign intraocular tumor that results from the proliferation of well-differentiated glial cells. MrGs develop because of a variety of causes. case report: We encountered a case of a 2-year-old male infant with loss of vision in the right eye. Enucleation was carried out due to an absolute glaucoma. Histologically, the vitreous body had been totally replaced by massively proliferated spindle cells, which had delicate fibrillary cytoplasm without nuclear atypia. Immunohistochemically, the cells were strongly positive for glial fibrillary acidic protein. these findings led to a diagnosis of massive gliosis. conclusion: Massive retinal gliosis (MrG) is a rare, benign intraocular tumor that results from the proliferation of well-differentiated glial cells. to our knowledge, this may be the first report of such an occurrence in a 2-yearold infant. It is important for ophthalmologists to be suspicious of a mass resistant to chemotherapy that resembles a rb in children.