We present a case of normal pressure hydrocephalus in a 70-year-old man with previously diagnosed systemic lupus erythematosus. Histological examination demonstrated the linear deposition of IgG, IgA, IgM, C(3) and C(1q) on the dura in the absence of inflammation or thrombosis that has previously been implicated in the aetiology of elevated pressure hydrocephalus in systemic lupus erythematosus. Our results suggest that the deposition of immunoglobulins and complement may play a pivotal role in an insidious manner in the pathogenesis of normal pressure hydrocephalus in systemic lupus erythematosus.