Abstract Many neurologic and psychiatric manifestations have been associated with systemic lupus erythematosus. Narcolepsy, currently hypothesized as related to an autoimmune process, has been rarely associated with systemic lupus erythematosus. We report a 36-year-old woman who presented with narcolepsy and who subsequently developed systemic lupus erythematosus. Excessive daytime sleepiness resolved after the administration of four intravenous bolus of cyclophosphamide and methylprednisolone followed by maintenance therapy with hydroxychloroquine, aspirine and prednisone. Narcolepsy should be included in the neuropsychiatric manifestations of systemic lupus erythematosus and it may have a parallel clinical course to the activity of the lupus.