Deep vein thrombosis(DVT) can occur on trops as short ad three to four hours even though it has been reported that long distance travelers are more susceptible to this insult. We present a previously healthy 17-year-old man who suffered from marded left leg pain and calf fullness after a long trip on a bus. Under a diagnosis of deep vein thrombosis of the left lower leg, he received intravenous heparin which was changed to oral coumadin for six months. He had had no further episodes after one yeaer of follow-up. To our limited knowledge, thrombotic episodes related to bus trips have not been reported in Taiwan where distances traveled are usually not long because of the size of the islnad. Therefore, physicians should keep this possibility in mind ans be aware of preventive measures.