Pulmonary hypertension comprises a heterogeneous collection of disorders that all collectively result in the development of elevated mean resting pressures in the pulmonary artery. Key pathobiological manifestations of pulmonary hypertension include pathologic vascular remodeling of the arteries and veins of the pulmonary vasculature and eventual load stress-induced failure of the right ventricle. Regardless of the upstream cause of pulmonary hypertension, there has been a growing recognition of both shared risk factors and similar pathophysiologic mechanisms that drive both cancer and pulmonary hypertension This book chapter discusses the existing literature that demonstrates similar multi-hit genetic mutations that can lead to both pulmonary hypertension and cancer, similar pathways that drive metabolic reprogramming of affected cells in both conditions, and abnormal responses to oxygen tension changes in the environment. Finally, this book chapter also discusses the existing literature that supports how cancer can itself drive pathologic pulmonary hypertension through increased venous thromboembolic risk, tumor metastasis, and because of novel cancer therapeutics.