Background: Left ventricular diastolic dysfunction in asymptomatic patients with diabetes mellitus may represent the early stage of diabetic cardiomyopathy even in patients without structural cardiac disease or systemic hypertension and have a preserved left ventricular systolic function. Objectives: To determine the prevalence of left ventricular diastolic dysfunction in asymptomatic patients with diabetes mellitus. Methods: A cross sectional study was carried out on 86 diabetics and compared with 65 age and sex matched controls. Detailed history, physical examination , specific investigations and transthoracic echocardiography study (including conventional pulse wave Doppler and tissue Doppler imaging) were done to assess the diastolic function. Results: Left ventricular diastolic dysfunction is more prevalent in diabetic patients comparing with control group (62.3% versus 12.8%, p<0.05) and this correlated independently with increasing age, duration of the disease and glycated hemoglobin level. Conclusion: Diastolic dysfunction can occur in diabetic patients even in young patients and those with shorter duration of disease. Tissue Doppler imaging, left atrial size and peak tricuspid regurgitation velocity are sensitive indices of LV diastolic dysfunction.