Heart failure (HF) affects approximately 2.1% of adult Australians and is associated with substantial morbidity and mortality. Approximately half of all patients with HF have HF with a preserved ejection fraction (HFpEF), which is increasing in incidence driven by an ageing population and an increasing prevalence of obesity and diabetes. Obesity drives HFpEF via multiple mechanisms, with a linear relationship between various anthropometric measures and the risk of developing HFpEF. Heightened diagnostic awareness is required to identify patients with obesity-associated HFpEF, given the availability of therapeutics that have been shown to improve quality of life and clinical outcomes, including sodium-glucose cotransporter 2 inhibitors, mineralocorticoid receptor antagonists, and glucagon-like peptide-1 agonist-based therapies. This review provides an overview of our current understanding of the impact of obesity on the development of HFpEF and outlines an approach to diagnosis and new therapeutic options.