Aim: The aim of the study was to evaluate the correlation between renal function and heart function/echocardiographic parameters and epicardial adipose tissue thickness (EATT), respectively. Material and methods: Fifty patients with type 2 diabetes (T2D) were included in this study. Several laboratory parameters were obtained (HbA1c, fasting blood glucose, LDL-cholesterol, creatinine) and eGFR was calculated. Anthropometric measurements were performed (weight, waist and hip circumferences, 4 skinfolds, based on which % body fat was calculated). Patients underwent echocardiographic assessment to evaluate structural and functional parameters, including EATT. Left ventricular mass (LVM) was calculated and the geometric changes of the left ventricle were evaluated. Results: Forty-six per cent of the patients had a LV ejection fraction (EF) <55% and 34% had diastolic dysfunction. There were no significant differences between the three eGFR groups with regards to metabolic parameters, but LVEF was lower (53.0 Å} 0.8%, 54.4 Å} 2.4%, and 55.2 Å} 1.5%, respectively) and EATT was higher (11.0 Å} 1.0 mm, 8.58 Å} 2.2 mm, and 7.63 Å} 2.6 mm, respectively) with a lower eGFR (p = 0.04). More patients with eGFR <90 mL/min/1.73 m2 had cardiac hypertrophy compared with those with eGFR ≥90 mL/min/1.73 m2 (p = 0.04). EATT correlated positively with several anthropometric parameters, e.g. weight (r = 0.309, 95% CI: 0.022 to 0.549, p = 0.03), BMI (r = 0.398, 95% CI: 0.123 to 0.616, p = 0.004), and negatively with LVEF (r = −0.496, 95% CI: −0.687 to −0.242, p = 0.0003) and eGFR (r = −0.293, 95% CI: −0.531 to −0.013, p = 0.04). In patients with LVEF <55% vs. ≥55%, the EATT was significantly higher (9.5 Å} 1.99 mm vs. 7.33 Å} 2.37 mm, p = 0.013). Conclusion: In patients with T2D decreased renal function was associated with lower LVEF and higher EATT. EATT was also higher in patients with reduced LVEF.