Bilateral, simultaneous optic nerve sheath infiltration as a manifestation of leukemia relapse is very rare. A 45-year-old woman with chronic myelogenous leukemia was successfully treated to cytogenetic bone marrow remission 1 year previously and maintained on imatinib. She developed total bilateral blindness with marked, bilateral optic disc edema and evidence of bilateral optic nerve infiltration on magnetic resonance imaging. Cerebrospinal fluid cytology confirmed central nervous system (CNS) blast crisis. She recovered visual acuity of 20/20 in the right eye, and 20/25 in the left eye with salvage systemic and intrathecal chemotherapy before radiation therapy. Our report underscores the importance of timely and aggressive intervention of blast crisis of the CNS and the need for CNS penetrating induction and maintenance therapy.