The case of an elderly patient who had chorea as an initial symptom of systemic lupus erythematosus (SLE) accompanied by antiphospholipid syndrome (APS) is reported. A 68-year-old woman suddenly developed chorea of her left arm and leg. Magnetic resonance imaging (MRI) of the brain demonstrated a focal lesion in the right caudate head, which showed hyperintensity on fluid-attenuated inversion recovery and diffusion-weighted imaging. This condition was thought to be a common form of vascular chorea, which is likely to occur in elderly individuals; however, the laboratory data of this patient finally fulfilled the diagnostic criteria of SLE and APS. Physicians should be careful in diagnosing elderly individuals simply as having a vascular chorea because this symptom can be the initial manifestation of SLE or APS.