Abstract: Although immune checkpoint inhibitors (ICIs) enhance the immune system’s capacity to destroy tumor cells, they can also induce a range of toxic responses that lead to cardiovascular damage. Among these adverse effects, ICI-associated myocarditis (ICI-M) has the highest morbidity and mortality rates, presenting a significant challenge in clinical practice. Cardiovascular magnetic resonance (CMR) is regarded as the "gold standard" for noninvasive assessment of cardiac structure, function, and tissue characteristics. While this imaging technique has advanced rapidly in recent years, with both domestic and international guidelines recognizing it as a crucial tool for evaluating ICI-M. This article provides a comprehensive overview of the pathological mechanisms underlying ICI-M, its diagnostic criteria, and the latest research developments in CMR and its clinical applications; it also discusses the most recent domestic and international guidelines and research findings.