Two patients with intracranial carotid injury, intracranial carotid occlusion (ICO) in one case and carotid-cavernous sinus fistula (CCF) in the other, diagnosed by transcranial Doppler sonography (TCD) are reported. The left ICO was diagnosed by TCD findings, showing a marked decrease in the flow velocity of the left middle cerebral artery (MCA) as compared to that of the right MCA and a normal flow velocity of the left ophthalmic artery. On the other hand, left CCF accompanied by significant steal was diagnosed by abnormal TCD flow patterns, i.e. an increased flow velocity in the left superior ophthalmic vein with an anterior direction, high flow velocity in the left cervical carotid artery, and decreased flow velocity in the left MCA. Both ICO and CCF were confirmed by angiography. Since TCD is non invasive and can be easily repeated at the bedside in critically ill patients, cerebral hemodynamics can be effectively evaluated. TCD is now commonly used to evaluate cerebral hemodynamics. Furthermore, in order to diagnose the acute phase of traumatic cerebral arterial injury by TCD, it is important to assess flow velocity information from many cerebral arteries using insonations.