A 63-year-old woman was admitted to our hospital with a 1-month history of visual field defect and reduced bilateral visual acuity. Neurological examination revealed enlargement of bilateral central scotoma and blurred vision, and brain MRI showed masses in the optic chiasma and right hypothalamus on Ti-weighted image with contrast enhancement. Although the patient was treated with high-doses of methylprednisolone four times, the masses spread to the right internal capsule and the vicinity of the right lateral ventricle. An open biopsy was performed and microscopic examination of the sample revealed lymphoplasmacytic lymphoma. Although primary central nervous system lymphoma (PCNSL) developing from the optic chiasma and hypothalamus is rare, PCNSL should be considered in patients with multiple lesions in the optic chiasma and hypothalamus.