Myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) is a newly described demyelinating disease. Ankylosing spondylitis (AS) is an inflammatory disease that predominantly affects the axial skeleton. Treatments for AS, such as tumor necrosis factor alpha (TNFα) inhibitors, may induce demyelination. We report the first case of MOGAD coexisting with AS and postulate a potential association with TNFα inhibitors. Further studies are needed to clarify the risk of demyelinating events following anti-TNFα therapy and to elucidate the relationship between MOGAD and AS.