A delayed massive traumatic hematoma in the corpus callosum is extremely rare. We report two cases with a delayed massive callosal hematoma caused by blunt head trauma. A massive callosal hematoma was diagnosed by computed tomography (CT) 2 weeks after a minor head injury in a 29-year-old man. A similar but larger hematoma developed 12 hours post-trauma with acute onset of consciousness disturbance in a 39-year-old man. Emergency CT angiography revealed no vascular pathologies in either case. The first patient was managed conservatively and recovered, whereas the second patient was treated surgically and died. The literature was reviewed regarding the possible mechanism of production of these lesions following head injury and therapeutic considerations are discussed.