Abstract: Interleukin-6(IL-6) is a pleiotropic cytokine, which plays an important role in the inflammatory response. There is increasing evidence that IL-6 also plays a very important role in the development of pulmonary hypertension, as evidenced by the fact that circulating levels of IL-6 are significantly elevated in pulmonary hypertension patients and animal models, that overexpression of IL-6 in mice can induce severe pulmonary hypertension, and that treatment targeting IL-6 can improve pulmonary hypertension. This paper reviews the research progress on the role of IL-6 in pulmonary hypertension and its mechanism at the molecular level, and introduce the current candidate regimens targeting IL-6 for the treatment of pulmonary hypertension, in order to provide a reference for clinical drug research and development for pulmonary hypertension.