Objective To investigate the appearance of 3.0 T magnetic resonance imaging (MRI) of acute myocarditis (AM) and the related clinical significance. Methods A total of 25 patients with AM were assigned to myocarditis group and 15 healthy volunteers were assigned to control group, all cases underwent cardiac MRI enhancement. The protocol included dual inversion recovery T2-weight null fat, diffusion weight imaging (DWI), cine, first-pass perfusion and delayed enhancement MRI. Results No positive abnormality was found in the 15 healthy volunteers. In the myocarditis group, 4 (16.0%) cases showed focal spot or patchy high signal in the left ventricular (LV) myocardium in dual inversion recovery T2-weight null fat. DWI in LV myocardium showed hyperintensity in 6 (24.0%) cases. Cine revealed reduced local ventricular wall motion in 4 (16.0%) patients. The ejection fraction (EF), LV end-diastolic volume and LV end-diastolic diameter in the 25 AM patients were(58.9±4.7)%, (147.0±28.9) mL, and (51.8±4.7) mm, respectively, which were not significantly different from those of the control group (P>0.05). One (4.0%) case had reduced local myocardial perfusion during first-pass perfusion. A total of 53 myocardial segments were involved in the 23 (92.0%) cases with subepicardial or/and mid-myocardial delayed enhancement, which mainly located in the septal zone and lateral zone. Ventricular wall motion abnormalities were consistent with delayed enhanced segments. Conclusion 3.0 T MRI can display the position, shape, range, degree and function of AM. Comprehensive analysis of cardiac MR sequences can provide imaging evidence for diagnosis and differential diagnosis of AM.