International audienceBACKGROUND: Congenital dysfibrinogenemia is a functional disorder of the fibrinogen that represents a rare cause of thrombophilia. AIM: To report a Tunisian case of the association dysfibrinogenemia and thrombosis. CASE: A woman with inherited dysfibrinogenemia associated with mild tendency to bleeding experienced a deep vein thrombosis of the lower-extremity at 26 years of age and a fatal pulmonary embolism a few years later. Paradoxically coagulation function of fibrinogen was markedly altered in vitro with a significantly prolonged prothrombin time, activated partial thromboplastin time and thrombin time, a functional fibrinogen level that was undetected and a severely impaired fibrin polymerisation. The thromboembolic events in the patient could be related to dysfibrinogenemia since the main causes of thrombophilia were excluded. CONCLUSION: Although it is rare, this cause of thrombophilia must not be misdiagnosed, systematic measuring of prothrombin time, activated partial thromboplastin time and functional fibrinogen might be helpful