Ocular involvement related to treatment with tumor necrosis factor alpha inhibitors is a rare adverse effect that may lead to irreversible outcomes. We illustrate through this report a case of optic atrophy under Etanercept in a patient with spondyloarthritis. The diagnosis was suspected due to visual acuity impairment, and was confirmed by ophthalmological examination. Although the TNF-blockers were discontinued and corticosteroids were administered, the follow-up examination did not reveal any improvement in visual acuity. This is a potential serious complication of TNF inhibitors that rheumatologists should recognize when monitoring patients with rheumatic diseases.