Intravascular large B cell lymphoma is a rare subtype of large cell lymphoma that is characterized by the proliferation of lymphoid cells within the lumina of small blood vessels. We report a 61-year-old male presenting paresis of both lower limbs, confusion and a history of weight loss. Magnetic resonance and CAT imaging studies showed multiple images of brain and cerebellar infarctions. Twenty days after admission, the patient died and the postmortem study demonstrated a multisystem intravascular large B cell lymphoma.