Introduction: In order to establish and use a national registry, several Hungarian hematology centers collected data of myeloproliferative neoplasia patients. Aim: The recent publication is an analysis of the data of registered essential thrombocythaemic patients. Method: an online electronic registry has been established, using 2008 World Health Organization's diagnostic criteria and thrombotic risk was evaluated according to Landolfi stratification. Results: Data of 350 essential thrombocythaemic patients from 15 Hungarian hematology centers entered up to the date of June 30, 2015 were used for analysis. Patients were followed up to (median) 6 years. The epidemiologic data (age, gender) and thrombotic events prior and after the diagnosis, were similar to the literature. The thrombotic events of anagrelide treated patient (n = 139) and the hydroxyurea + aspirin treated patients (n = 141) have been compared. The major arterial and venous events were similar between the groups, but there were fivefold less minor arterial and venous events in the anagrelide group (p < 0.001). Thrombotic incidence after diagnosis were influenced only by medication and thrombotic events before the diagnosis. Conclusions: Anagrelide significantly decreased the number of patients experiencing minor arterial and minor venous thrombosis, vs hydroxyurea + aspirin. Despite of the treatment the risk of thrombotic events after diagnosis remained high, and was significantly increased in patients with thrombosis before diagnosis.