INTRODUCTION: Sweet's syndrome is a multi-system inflammatory disorder characterised by painful skin lesions and aseptic neutrophilic infiltration of various organs. We describe a case of Sweet's syndrome with aseptic meningitis in association with Crohn's disease (neuro-Sweet syndrome). This association has never been previously reported. CASE PRESENTATION: A 47-year-old Caucasian male with known Crohn's disease presented with headache, fever and skin lesions resembling erythema nodosum. The cerebrospinal fluid revealed leukocyte pleocytosis and dominant neutrophils, but cultures were negative. A skin biopsy revealed neutrophilic dermatosis compatible with Sweet's disease. The patient made a prompt recovery without the use of corticosteroids. CONCLUSION: Because of its multisystem nature, Sweet's syndrome may present diagnostic difficulty to specialists. Correct diagnosis by skin biopsy will prompt appropriate treatment.