The aim of this study was to evaluate clinical and echocardiographic characteristics of patients with diabetic cardiomyopathy. The study included 72 patients, divided into two groups. The experimental group consisted of 32 diabetics, while 40 gender and age-matched healthy subjects were in the control group. In the experimental group there were 17 patients with insulin-dependent diabetes mellitus, and 15 patients with non-insulin-dependent diabetes mellitus. The average duration of diabetes mellitus was 9.53 years. All the patients underwent the following diagnostic procedures: standard laboratory tests, 12-lead ECG, chest X-ray, 24-h Holter ECG, and complete echocardiographic examination. More frequent appearance of ventricular rhythm disturbances (65,6% vs. 47,5%), increased heart rate (78.3 ± 8.2 vs. 72.1 ± 4.6 beats per minute), and alteration of diastolic (56.25% vs. 12.5%) and systolic function (43.8% vs. 0%) was registered in patients with diabetes, compared to the control group. Experimental group was divided, according to their left ventricular dimensions, into two subgroups: the subgroup with normal left ventricular dimensions, and the subgroup with the increased left ventricular dimensions. Patients with the increased left ventricular dimensions not only had significantly lower ejection fraction (37.4 ± 7.0 vs. 61.3 ± 4.2%), but also had significantly longer duration of diabetes (12.6 ± 5.8 vs. 8.01 ± 3.01 years), worse quality of glycoregulation (13.1 ± 2.5 vs. 10.4 ± 2.1%), and higher Shapiro’s microvascular complications index (2.7 ± 1.26 vs. 0.68 ± 0.56). High degree of correlation was also found between the duration of diabetes left ventricular ejection fraction (-0.86), and left ventricular mass (0.86). The similar level of correlation was shown with Shapiro’s index (-0.77 and 0.88), as well as with morning glycaemia (-0.57 and 0.41). According to the obtained results it could be concluded that the changing rate of diabetic cardiomyopathy was in direct correlation with the quality of diabetes control, the duration of diabetes, and the presence of complications in other organs.