<h4>Background</h4>Because the venous thromboembolisms (VTEs) due to the coagulation factor V R506Q (FV Leiden) mutation is often seen in Caucasians, the VTE onset in Japan has not been reported.<h4>Case presentation</h4>A 34-year-old man from north Africa experiencing sudden dyspnea went to a hospital for advice. Here, F5 is linked to venous thromboembolism.