Abstract: Heart failure with preserved ejection fraction (HFpEF) is defined as having a left ventricular ejection fraction (LVEF) of ≥50% accompanied by elevated natriuretic peptide (BNP) levels or other evidence of congestion. HFpEF is characterized by high morbidity and mortality rates and has surpassed heart failure with reduced ejection fraction (HFrEF) to become the predominant form of heart failure. This article reviewed the definition, epidemiology, classification, diagnosis, pathology, comorbidities, and treatment of HFpEF, providing evidence for clinical research.