The aim of this prospective study was the assessment of left ventricular and right ventricular diastolic function in patients on hemodialysis (HD) and the correlation of this function with the duration of HD. The study included 42 patients (22 females and 20 males) with chronic renal failure (CRF), treated with HD, and 40 healthy subjects (24 females and 16 males) with no history of cardiovascular disease and with normal renal function, who constituted the control group. The groups were matched for age and sex. All study patients and control subjects underwent detailed history taking and physical examination. They also underwent electrocardiogram, echocardiography and biochemical and hematological blood analyses. Significant differences were noted between the two groups in the two-dimensional and M-mode echocardiography findings concerning aortic root dimension, transverse diameter of the left atrium, thickness of the interventricular septum, thickness of the left ventricular posterior wall, left ventricular diastolic diameter, left ventricular systolic diameter, shortening fraction, ejection fraction as well as findings from the pulse Doppler study, including E wave, A wave, E/A ratio, deceleration time of E wave (DT-E), acceleration time of E wave (AT-E), tricuspid E and A waves (E tr and A tr ) and E tr /A tr , ratio. There were significant changes in HD patients without arterial hypertension as well in the control group subjects. Our study suggests that the left ventricular and left atrial dimensions as well as the left ventricular wall thickness are augmented in patients with CRF treated with HD compared with the control group. Additionally, the left and right ventricular diastolic function is also reduced in these patients. These differences were also noted in patients with CRF without arterial hypertension. Left ventricular diastolic dysfunction had no correlation with the duration of HD.