Heart failure is characterized by abnormal β-adrenergic receptor (β-AR) activation and mitochondrial dysfunction. In heart failure, overactivation of β-AR mediates key pathological processes in cardiomyocytes, including oxidative stress, calcium overload and metabolic abnormalities, which subsequently lead to inflammation, myocardial apoptosis and necrosis. Mitochondria are the core organelles for energy metabolism, and also play a vital role in calcium homeostasis, redox balance and signaling transduction. Moderate β-AR activation is conducive to maintaining mitochondrial homeostasis and physiological cardiomyocyte function. However, β-AR overactivation in heart failure disrupts mitochondrial function through multiple mechanisms. Therefore, our review aims to elucidate how β-AR regulates mitochondrial function, particularly under sympathetic stress, impacting oxidative stress, apoptosis, necrosis, and metabolic imbalance. By describing these mechanisms, we seek to propose new insights and therapeutic targets for the prevention and treatment of heart failure.