Purpose To describe a case of leukemic infiltration of bilateral optic nerves and retina as a site of relapse in a child with T-Cell Acute Lymphoblastic Leukemia (ALL). Observations We report a 7 year old female who presented one year following initial treatment for T-Cell ALL with visual acuity impairment, bilateral optic nerve infiltration and infiltration of the retina of both eyes. OCT demonstrated subretinal fluid in both eyes, which eventually resolved, and perivascular hyperreflectivity within the inner retinal layers. She was treated with systemic and intrathecal chemotherapy, total body and orbital radiation and eventual bone marrow transplantation with notable improvement in vision and regression of retinal and optic nerve findings. With continued remission, there was notable outer retinal thinning, specifically of the photoreceptors in the right eye. Conclusions and importance Leukemic abnormalities of the eye are not uncommon, however optic nerve and retinal infiltration are rare manifestations. Leukemic infiltrates of the retina can be detected by OCT despite normal funduscopic examination and monitored for improvement. The optic nerve and other ocular tissues are considered a pharmacologic sanctuary and thus, the optic nerve can be a site of relapse in leukemia. The use of radiation therapy is a helpful adjunct with systemic, intrathecal chemotherapy and stem cell transplantation in obtaining clinical remission and visual acuity improvement.