Blunt injury to the carotid artery is rare but may produce a devastating outcome with longterm morbidity. Initial recognition by clinicians is often difficult because of the diverse clinical manifestations, the delay in presentation of symptoms, and the associated multi-organ system injuries that accompany carotid injury. Early diagnosis and successful management of traumatic carotid artery injury require a high index of clinical suspicion. We report herein a 20-year-old male victim of internal carotid artery injury induced by a motorcycle accident, who initially presented with a clear consciousness and had normal computed tomogram (CT) of brain. Two days after injury, the patient suffered from left hemiplegia and coma. The follow-up brain CT showed acute infarction of right cerebrum and severe cerebral edema. Emergency craniotomy for brain decompression and anticoagulation therapy was carried out. After a three-month treatment, he was discharged and underwent regular follow-up in the outpatient department. Six months later, the patient had intact awareness but remained in a left-sided hemiparetic state.