We present a patient with relapsing polychondritis who presented with findings of lateral medullary syndrome, known as the syndrome of Wallenberg, produced by infarction of a wedge of lateral me dulla lying posterior to the inferior olivary nucleus. Angiographic examination showed complete occlusion of the right posterior inferior cerebellar artery and segmental narrowings in the basilar artery. We believe that the angiographic findings were based on an underlying vasculitis because of his relapsing polychondritis. This is the first case of relapsing polychondritis with angiographically demonstrated posterior inferior cerebellar artery involvement. Although this syndrome is usually a result of atherosclerosis, our case suggests that vasculitis must also be considered because it may respond to treatment with corticosteroids.