A 43-year-old man came to our hospital with trauma from a fall. Two weeks after the injury, CT scanning revealed an IVC thrombus. Unfractionated heparin and warfarin were administered, though were not highly effective. The anticoagulant was changed to rivaroxaban and placement of an IVC filter was also performed. One month later, the thrombus had disappeared. Development of an IVC thrombus due to blunt abdominal trauma is uncommon. In such cases, diagnosis is often delayed because there are no specific findings, thus repeated CT scanning may be necessary over time. For treatment, anticoagulation therapy and a thrombectomy are often selected.