Hypertrophic cardiomyopathy (HCM) is a genetic disease with heterogeneous clinical presentation and prognosis. Within the broad phenotypic expression of HCM, there is a subgroup of patients with a left ventricular (LV) apical aneurysm, which has an estimated prevalence between 2% and 5%. LV apical aneurysm is characterized by an area of apical dyskinesis or akinesis, often associated with regional scarring. To date, the most accepted pathomechanism of this complication is, in absence of coronary artery disease, the high systolic intra-aneurysmal pressure, which, combined with impaired diastolic perfusion from lower stroke volume, results in supply–demand ischemia and myocardial injury. Apical aneurysm is increasingly recognized as a poor prognostic marker; however, the efficacy of prophylactic anticoagulation and/or intracardiac cardioverted defibrillator (ICD) in improving morbidity and mortality is not yet clearly demonstrated. This review aims to elucidate the mechanism, diagnosis and clinical implication of LV aneurysm in patients with HCM.