Immune checkpoint inhibitors (ICIs) represent a novel class of cancer therapy that has significantly extended patient survival compared to traditional treatments like chemotherapy. In addition to improving mortality, ICIs also enhance quality of life by avoiding many of the common side effects associated with chemotherapy, which indiscriminately targets both healthy and cancerous cells. ICIs work by enhancing the immune system’s ability to target cancer cells, primarily through three pathways: cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), programmed cell death protein 1 (PD-1), and programmed death-ligand 1 (PD-L1). These agents can be administered as monotherapy or in combination, with each approach presenting a unique side effect profile linked to immune-related adverse events (irAEs) due to immune system modulation. These side effects can affect multiple organs, including the heart, where myocarditis is the most common cardiovascular manifestation. While the exact pathophysiology of ICI-induced myocarditis is not well understood, molecular mimicry may play a role. Timely diagnosis of ICI-induced myocarditis is crucial, as it has significant implications for patient mortality. The diagnosis of ICI-induced myocarditis is based on clinical presentation and cardiac evaluation, including measurements of troponin and BNP, as well as EKG, echocardiography, cardiac MRI (CMR), and, in severe cases where the cause remains unclear, endomyocardial biopsy. Management typically involves discontinuing the ICI therapy and initiating immunosuppressive treatment. A wide range of immunosuppressive therapies can be considered, starting with corticosteroids as the first-line treatment. Other options include infliximab, tocilizumab, mycophenolate mofetil, etc. The potential side effects of ICIs can be life-threatening and must be well understood by physicians. It is essential for healthcare providers to distinguish cardiac irAEs from other common conditions, such as myocardial infarction.