Studies on diagnoses and treatments based on microRNAs ( miRNA/ miR) are increasing. However, currently most studies in the field of cardiovascular diseases are limited to the application of miRNAs in the left ventricle, and few studies have involved the right ventricle. Therefore, this review examines the latest literature and summarizes the application of miRNAs in right heart disease. We first review intraventricular-specific expression of miRNAs and their application in right heart-related disease. Second, the application status of circulating miRNAs in patients with pulmonary hypertension and right ventricular failure is discussed. Finally, the potential of miRNA modulators in the treatment of pulmonary hypertension and their beneficial effects on the right ventricle are described. We hope that the continued accumulation of evidence on miRNAs in the right heart will help improve treatment for patients with pulmonary hypertension and right ventricular disease.