The occurrence of heart electrophysiology dysfunction or/and muscle damage is referred to as cardiotoxicity. The heart weakens and becomes less efficient at pumping and hence circulating blood. Cardiomyopathy can be caused by a variety of factors, including viral infections, diseases such as diabetes, ischemia, hypertension, obesity, radiation therapy, antipsychotic drugs, cytotoxic drugs, most notably chemotherapeutic agents; antitumor antibiotics, monoclonal antibodies, tyrosine kinase inhibitors, platinum-based compounds, microtubule inhibitors, vinca alkaloids, antimetabolites, proteasome inhibitors, topoisomerase inhibitors, alkylating agents, corticosteroids. This chapter focuses on the mechanisms of cardiotoxicity, animal models and transgenic methods used in studies, and the effects of therapeutic agents on cardiotoxicity.