The clinical and therapeutic features of 18 delayed traumatic intracerebral hematomas (DTICH) were compared with those of 84 primitive traumatic intracerebral hematomas in order to determine the origin of this complication. This retrospective study found that: DTICH usually occurs the first week after trauma, but could happen several weeks later; patients with skull fractures are at higher risk (p less than 0.01); osmotherapy as well as barbiturate therapy seem to have no influence on this complication; craniotomy (or craniectomy) appears to be a significant factor in the cause of DTICH (p less than 0.05). The pathogenesis of DTICH could be the evolution of delayed necrosis in vessel walls from the contused area which frequently bleed after the evacuation of an extracerebral hematoma. On the other hand the cause of a DTICH after conservative therapy remained unclear.