In clinical practice, myocardial ischemia-reperfusion (MI/R) is widely used for the treatment of myocardial infarction, but reperfusion may cause secondary damage to the myocardium. The early stages of MI/R lesions are associated with ferroptosis, however, in vivo, noninvasive visualization of ferroptosis in MI/R using molecular imaging methods remains difficult. We report an Fe3O4-based probe for magnetic nanoparticle imaging of ferroptosis (feMPI) by exploiting transferrin receptor 1 (TfR1) as a typical biomarker. The feMPI, based on the TfR1-targeting and cell-penetrating peptides (CPPs) dual-targeted probe, detects cardiac injury ~48 h in advance and quantitatively determines damage degree during post-MI/R ventricular remodeling, as compared to existing clinical imaging detection methods. This new imaging strategy compensated for the difficulty in detecting I/R damage during cardiac remodeling. These findings are notably consistent with the commonly used clinical biochemical indicators in the early stage of MI/R. In addition, optical and MI/R imaging was integrated as a multimodal to precisely monitor the occurrence and development of MI/R-induced cardiac injury. This study proposes a powerful imaging-effect-based feMPI strategy for the precise assessment of MI/R-induced cardiac injury, which may help elucidate diagnostic methods for ferroptosis-related heart diseases.