An 18-month-old infant diagnosed as having endomyocardial fibrosis by echocardiography is presented. Most patients with endomyocardial fibrosis reported in the literature are either older children or adults. To our knowledge, our patient was the youngest ever to have been reported. Echocardiographic studies showed obliteration of the left ventricular apex and increased echo reflectance at the left ventricular endocardium and subendocardium. The left atrium and right ventricle were significantly enlarged. Doppler echocardiography showed minimal mitral, but significant tricuspid regurgitation. In regard to the contribution of echocardiography in the diagnosis, we recommend this method for suspected cases. Contrary to the other patients reported, there was no thickening of the atrioventricular valves. Mitral valve insufficiency was related to the restriction of the ventricular filling rather than to valve involvement occurring with the disease.