Philadelphia chromosome-negative myeloproliferative neoplasms (Ph-MPN) mainly include 3 types, that is, primary myelofibrosis (PMF), polycythemia vera (PV), and primary thrombocythemia (PT). The Janus kinase1/2 (JAK1/2) inhibitor ruxolitinib has been at the heart of PMF treatment since 2011. Before this, allogeneic hematopoietic stem cell transplantation is the only possible treatment for PMF, but it is prohibitive for most patients because of lack of matching or expensive aspects. As the targeted drug for PMF, ruxolitinib aims at the pathogenesis of PMF, so as to fundamentally control the disease and improve the clinical symptoms of patients. In addition to treating PMF, it also plays a good role in PV or PT patients with hydroxyurea resistance or intolerance.