We screened 134 consecutive patients with von Willebrand disease (VWD) (106 type 1, 26 type 2, and 2 type 3 VWD) for the most important inherited prothrombotic risk factors. One hundred eight patients (80.6%) were positive for at least one of the prothrombotic risk factors screened for. A high prevalence of prothrombin G20210A (10.5%) and factor V Leiden (11.9%) mutations was found with allele frequencies of 5.2 and 6%, respectively. Three carriers of multiple prothrombotic gene mutations experienced a thrombotic event. Our study suggests that the recent evidence of an association between inherited thrombotic and hemorrhagic disorders also holds true in VWD patients.