The zebrafish heart has the capacity to regenerate after ventricular resection. Although this regeneration model has proved useful for the elucidation of certain regeneration mechanisms, it is based on the removal of heart tissue rather than on tissue damage. We recently characterized the cellular response and regenerative capacity of the zebrafish heart after cryoinjury (CI), an alternative procedure that more closely models the pathophysiological process undergone by the human heart after myocardial infarction (MI). After anesthesia, localized CI with a liquid nitrogen-cooled copper probe induced damage in 25% of the ventricle, in a procedure requiring <5 min. Here we present a detailed description of the technique, which provides a valuable system for the study of the mechanisms of heart regeneration and scar removal after MI in a versatile vertebrate model.