Patients with cancer are at increased risk of cardiovascular disease, with a reported prevalence of acute coronary syndrome (ACS) ranging from 3% to 17%. The increased risk of ACS in these patients seems to be due to the complex interaction of shared cardiovascular risk factors, cancer type and stage, and chemotherapeutic and radiotherapy regimens. The management of ACS in patients with cancer is a clinical challenge, particularly due to cancer’s unique pathophysiology, which makes it difficult to balance thrombotic and bleeding risks in this specific patient population. In addition, patients with cancer have largely been excluded from ACS trials. Hence, an evidence-based treatment for ACS in this group of patients is unknown and only a limited proportion of them is treated with antiplatelets or invasive revascularization, despite initial reports suggesting their beneficial prognostic effects in cancer patients. Finally, cancer patients experiencing ACS are also at higher risk of in-hospital and long-term mortality as compared to non-cancer patients. In this review, we will provide an overview on the available evidence of the relationship between ACS and cancer, in terms of clinical manifestations, possible underlying mechanisms, and therapeutic and prognostic implications.