Cancer incidence in patients with recurrent unprovoked venous thromboembolism (VTE) is much higher than after a first event, but the incidence of myeloproliferative neoplasms (MPN) in this situation is still unknown. We tested for JAK2V617F and calreticulin mutants, 372 DNA samples of patients treated for (VTR). Among these patients, 10 (2.7%) were carrying JAK2V617F mutation and none of them any of the calreticulin (CALR) mutations. Among the 19 patients who had VTE recurrence under vitamin K antagonists, 4 patients (21.0%) were positive for JAK2V617F. Despite the identification of JAK2V617F mutation, only three patients were diagnosed for MPN despite a median follow-up of 4 years. We showed that the screening for JAK2V617F not CALR mutations should be helpful in this indication especially if recurrence happened under VKA therapy.