The authors evaluated the main clinical and evolutive aspects of heart involvement in the newborn of diabetic mother (IDM). We studied the files of 35 IDM in a 4 years period; they were investigated the first week of life and at 6-12 months (18 cases). Most of the patients were asymptomatic/signs of extracardiac suffering; 15 had a systolic murmur. ECG: left ventricle (LV) hypertrophy (8) and LV repolarization disturbances (19 cases). Chest X-ray: cardiomegaly (9 cases). Echocardiography: hypertrophic cardiomyopathy (HCM), especially septal (25 cases, 71%); LV diastolic dysfunction (19-35) and normal systolic function; pulmonary hypertension (3), other congenital heart diseases (8 cases). The control revealed the alleviation of the LV walls size and LV diastolic function. The high incidence of the cardiac manifestations in IDM and the risk of occurrence of some severe problems, require a complete cardiological exam from the first few days of life and a follow-up schedule until the normalization of the cardiac parameters.