Pre-B cell acute lymphoblastic leukemia (ALL) is a hematologic malignancy that arises from overproduction of immature lymphoid cells. ALL has a propensity for recurring in the bone marrow and/or extramedullary sites following complete remission. We present the case of a young male with a history of pre-B cell ALL who presented with leukemic recurrence isolated to the optic nerve. Transvitreal fine needle aspiration biopsy followed by transconjunctival optic nerve biopsy confirmed the diagnosis of ALL relapse and should be considered helpful diagnostic tools in the setting of suspected optic nerve malignancy with otherwise negative workup.