The first clinical case of transient traumatic locked-in syndrome is presented. The locked-in state lasted for 3 months. The patient's neurologic deficit and the abnormal auditory evoked responses pointed to a lesion involving the left pons and ventral midbrain. The locked-in syndrome caused by a traumatic damage of the brain stem structures can be transient and thus it may have a better prognosis than the locked-in syndrome secondary to the occlusion of the basilar artery.