Immunotherapy has revolutionized the treatment of various cancers leading to a clear survival benefit with cured or long-surviving patients. Atherosclerosis and cancer share risk factors and molecular mechanisms and have as their common thread a state of chronic inflammation linked to a deregulation of the immune system. A growing body of evidence is accumulating on the potential worsening effect of immune checkpoint inhibitors on atherosclerosis, with subsequent worsening of patients' long-term cardiovascular risk. The molecular pathways implicated in the growth and deregulation of atherosclerotic plaques seem to be the same (CTLA-4, PD-1, PD-L1) as those on which the anti-tumor effect is exerted. Owing to the increasing number of cancer patients treated with immunotherapy and the improved survival with the possibility of prolonged disease control, it is necessary to know the potential increase in cardiovascular risk for atherosclerosis-related events and to establish all prevention measures to reduce it.