Endocardial fiborelastosis (EFE) is a common infantile myocardiosis. The pathogenesis of EFE may be associated with viral infection, genetic factors, immune factors and endocardial dysplasia. The fundamental pathological changes of EFE include hyperplasia of endocardium elastic fibers and collagen fibers. Acute EFE is a frequent type. Clinical manifestations of EFE are non-specific and children with EFE mainly present with congestive heart failure. Echocardiography is very helpful to the diagnosis of EFE. It is necessary to differentiate EFE from pneumonia complicated by acute congestive heart failure, viral myocarditis and anomalous origin of the left coronary artery. Treatment is meant to control symptoms of congestive heart failure. Patients who respond well to digitalis and have good medication compliance have a favorable prognosis.