On rare occasions, patients infected with human immunodeficiency virus (HIV) can develop a disorder similar to chronic progressive external ophthalmoplegia (CPEO) while undergoing long-term treatment with antiretroviral therapy. Orbital imaging may help explain the pathogenesis of this abnormality.In this case series, 5 adult patients who presented with a CPEO-like disorder after more than 10 years of antiretroviral therapy and who underwent T1-weighted high-resolution magnetic resonance imaging (MRI) of the orbits and brain were retrospectively identified. Patients also were screened for acetylcholine receptor antibody levels.All patients had bilateral external ophthalmoplegia and blepharoptosis. Acetylcholine receptor antibody titers were not increased. Brain MRI was unremarkable. Orbital MRI showed patchy bright signal inside the extraocular muscles that had conserved volume.Patients with HIV under long-term antiretroviral therapy may develop functional abnormalities of extraocular muscles that are structurally normal in size, that is, changes are similar to those observed in the orbital MRIs of patients with CPEO. This constellation of signs and symptoms suggests a possible role of HIV disease or antiretroviral therapy in the CPEO-like syndrome observed in some HIV-infected individuals.