BackgroundTo report a rare case of extranodal natural killer/T-cell lymphoma (ENKTL), nasal type related to extensive ocular tissue, including conjunctiva, ciliary body, vitreous and retina. Case presentationA 52-year-old woman who had been treated by radiotherapy for ENKTL, nasal type in the right nasal cavity presented with a dramatic deterioration of vision in right eye. Physical and accessary examination showed extensive ocular tissue related, including conjunctiva, ciliary body, vitreous and retina. Vitreous specimen and conjunctiva biopsy revealed the presence of ENKTL, nasal type in the right eye. She was treated with systemic and ophthalmic chemotherapy, her ocular symptoms significantly improved, and systemic condition remained stable 7 months after the diagnosis.ConclusionsExtranodal natural killer/T-cell lymphoma, nasal type is an aggressive disease and may relate extensive ocular tissue and course dramatic vision deterioration. It is important to observe ocular related and begin aggressive combined therapy as early as possible after diagnosis.