Both Coxsackie infection and multiple sclerosis (MS) are rare in human immunodeficiency virus (HIV) infection. We report a 35-year-old woman with known HIV infection of 12 years' duration and a clinical illness of 4 years' duration consistent with MS. The latter was characterized by optic neuritis, bilateral abducens palsies, recurrent Bell's palsy, hemiparesis, and ataxia coupled with white matter abnormalities on magnetic resonance imaging (MRI). Autopsy revealed Coxsackie B meningoencephalitis; no other infectious disease were detected and no histopathological features of MS were evident. We suggest that the relapsing-remitting neurological disease in this patient was the consequence of Coxsackie B meningoencephalitis. This is the first case report, to the best of our knowledge, of an enteroviral meningoencephalitis complicating human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS).