Pulmonary hypertension (PH) is a serious cardiovascular disease, which is characterized by an increase in pulmonary vascular resistance and arterial pressure. Its pathological mechanism is complex, involving a variety of immune-inflammatory responses and signal transduction pathways. This article reviews the latest research advancements in PH from pathological mechanism to clinical management, with particular attention to immune-inflammatory response and its signal transduction. Firstly, this article deliberates on the pathological mechanism of PH, concentrating on the pivotal role of immune cells and inflammatory factors in the progression of the disease. Subsequently, the clinical manifestations, diagnostic approaches, treatment strategies, daily management, and prevention measures of PH were elaborated in detail, with specific emphasis on innovative treatment plans from the perspective of immunity. The conclusion section recapitulates the main findings of the current study and proposes directions for future research aimed at providing new viewpoints and strategies for deeper comprehension and efficacious treatment of PH.