A dedicated guideline to the evaluation of cardiovascular toxicity in pediatric cancer by cardiac magnetic resonance imaging (MRI) does not exist. Therefore, the aim of this document is to provide guidance in the utility, acquisition, and interpretation of cardiac MRI in childhood cancer survivors. We will focus on briefly defining cardiovascular toxicity in childhood cancer survivors and reviewing the key aspects of a detailed cardiac MRI study in a patient with acute versus chronic cardiovascular toxicity. We intend for this document to serve as a guideline on how to perform a cardiac MRI to evaluate cardiac toxicity based on a review of the current literature. There will be a review of a detailed cardiac MRI protocol (bi-ventricular volumes and mass, myocardial strain, tissue characterization, late gadolinium enhancement, and 4 Dimensional/4D flow) in the assessment of cardiovascular toxicity from cancer therapy. It is hoped that the availability of a standardized approach to cardiac MRI assessment in childhood cancer survivors improves cardiovascular care in this population.