Three cases of internal carotid artery (ICA) dissection due to trivial trauma were reported. A 14-year-old, previously healthy, girl developed left hemiparesis after jogging. MRI sh owed cerebral infarction in the right basal ganglia and the MR angiography (MRA) revealed luminal narrowing of the right ICA as well as pseudolumen at the origin of the right ICA. She was treated with antithrombotic therapy. Follow-up MRA demonstrated normal signal in the right ICA. A 23-year-old woman admitted to the hospital because of minor facial injury due to a traffic accident. Although she had no apparent symptom, follow-up CT, one day after presentation,. showed cerebral infarction in the right basal ganglia. Angiography showed diminished luminal diameter of the right ICA. She was treated with antithrombotic therapy and follow-up angiography showed reconstitution of normal lumina of the right ICA. A 34-year-old woman was referred to our hospital because of transient ischemic attack following swimming. Neurological examination was normal and MRI did not show any ischemic lesion. MRA revealed diminished signal in the left ICA as well as string and pearl sign at the origin of the left ICA. She was treated with antithrombotic therapy, and follow-up angiography showed normalization of the left ICA. Cervical ICA dissection due to trivial trauma usually appears as an eccentric tapered stenosis arising at the origin of the ICA and resolves with complete or excellent recovery in most cases. Surgical or endovascular treatment should be reserved for patients who have persistent symptoms of ischemia despite adequate antithrombotic treatment.