BACKGROUND: To present 2 patients with myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease with unilateral orbital inflammation, optic nerve head edema, and abnormalities of the optic nerve and nerve sheath on imaging. We review the most current literature on this important and uncommon clinical phenotype. METHODS: A case report of 2 patients and a comprehensive review of the relevant literature on orbital inflammation in MOG antibody-associated disease (MOG-AD). RESULTS: Two patients presented with decreased vision and unilateral orbital inflammation. Both had optic nerve head edema and abnormalities of the optic nerve and nerve sheath on imaging. The patients were treated with immunosuppressants and had improvement of vision changes as well as their orbital inflammatory signs. MOG antibody was positive in high titers in both patients. Only 3 other cases of orbital inflammation associated with MOG antibody have been described. In all cases, orbital signs responded rapidly to intravenous methylprednisolone, but the improvement in visual acuity was variable and less robust. CONCLUSION: Orbital inflammation is a unique and underrecognized phenotype of MOG-AD with only a few reports in the literature. In patients who present with vision loss and orbital inflammation, MOG-AD should be considered in the differential.