To evaluate the frequency of jak2v617f mutation and analyze its correlation with clinical features of primary thrombocythemia (PT) patients, the mutation was detected by allele specific polymerase chain reaction (AS-PCR), the clinical and laboratory data in 66 PT patients with and without jak2v617f mutation were compared and clinical features of these PT patients were retrospectively analyzed. The results showed that among 66 patients, 27 patients (41%) had the mutation. The patients carrying the mutation displayed higher bone marrow erythropoiesis (26.9%+/-9.4% vs 16.3%+/-8.7%, p<0.05), higher ratio of granulopoiesis/erythropoiesis (2.9+/-1.8 vs 5.2+/-2.9, p<0.05) and higher incidence of microvascular disturbances (29.6% vs 5.1%, p<0.05). However, the age, gender, leukocyte and platelet counts, hemoglobin level, bone granulopoiesis, splenomegaly, history of thrombosis and hemorrhage had no difference between patients with and without the mutation. It is concluded that the frequency of jak2v617f mutation in primary thrombocythemia patients is 41%. The presence of the jak2v617f mutation is associated with a higher bone marrow erythropoiesis in primary thrombocythemia patients at diagnosis.