There are few reports of neuro-ophthalmologic involvement in Churg-Strauss syndrome (CSs). We described a case of unilateral optic atrophy in a 46-year-old-white man with CSs. The patient had severe bronchial asthma, allergic rhinitis, hypereosinophilia (8%) and peripheral neuropathy. The visual acuity in his right eye was light perception. At the biomicroscopy there were no corneal and conjunctival lesions. Ophthalmoscopy showed a pale right optic disc and fluorangiography revealed a marked hypofluorescence of the disc at early phase of angiogram. We suggested that the optic atrophy was most probably due to vasculitis of the ciliary arteries.