Abstract: Objective To determine the prevalence of sleep disordered breathing (SDB) in elderly patients with chronic congestive heart failure (CHF) and explore the relations between SDB and left ventricular function. Methods By means of polysomnography , 56 elderly patients with CHF were divided into non-SDB, mild SDB, moderate SDB, and severe SDB groups, and the left ventricular ejection fraction (LVEF) was measure by 99Tc equilibrium radionuclide angiography. Results In the 56 elderly patients with CHF, 38 (67.9%) had SDB, including 12 (21.4%) mild SDB, 14 (25.0%) moderate SDB, and 12 (21.4%) severe SDB patients. Thirty (53.6%) of the 56 patients with CHF had obstructive sleep apnea (OSA), 4 (7.1%) had central sleep apnea and 22 (39.2%) had mixed sleep apnea. The moderate and severe SDB groups had lower minimum arterial oxyhemoglobin saturation during sleep than the non-SDB groups, and the apnea-hyponea index was closely related to LVEF (r=-0.74, P<0.01). Conclusions The prevalence of SDB, predominantly OSA, is high in elderly patients with CHF. Moderate and severe SDB might affect the left ventricular function in these patients, who require polysomnography monitoring.