Guidelines on heart disease prevention have repeatedly defined subjects with diabetes as a group at high risk for heart disease. The question of a specific diabetic heart muscle disease "diabetic cardiomyopathy" has caused much debate.In the present study, we studied 30 children and adolescents with type 1 diabetes. They included 18 males and 12 females, their ages ranged from 4.68 to 21.17 years, had a diabetes duration of 0.51 to 14.28 years, and had different degrees of glycemic control. Fourteen healthy age and sex matched children and adolescents were taken as the control group.M-mode, 2-D and Doppler was used for echocardiographic examination of the patients and controls. Cardiac dimensions as well as ventricular systolic function showed no significant difference when compared to the controls. However, ventricular diastolic function showed a significantly higher mean mitral and tricuspid peak A velocities compared to the controls. Also mean mitral E/A was significantly lower in the diabetics.Basal HR was increased in 33.3% of the diabetics, and this showed a significant positive correlation to mitral peak A velocity and a negative correlation to mitral E/A.