Abstract: Pulmonary hypertension is a group of physiopathologic syndromes that are induced by different diseases and are featured with high pulmonary artery pressure and higher resistance of pulmonary vasculature. The pathogenic mechanism of pulmonary hypertension is still not completely known. But recently,with the advanced understanding of the mechanism of pulmonary hypertension, the studies at the molecular level show that some factors which induce pulmonary vasodilation, vasoconstriction and remodeling play a very important role during the process of the formation of pulmonary hypertension. This article mainly reviews the mechanism of hypoxia-inducible factor-1, urotensin Ⅱ, calcitonin gene related peptide, angiopoietin-1 during the process of the formation of pulmonary hypertension.