Background Researchers still do not reach the consensus on the incidence,characters and the prognostic value of pericardial effusion (PE) in patients with chronic heart failure (CHF).This study is to investigate the incidence,characters and the prognostic value of pericardial effusion (PE) in patients with CHF.Methods One thousand one hundred and eighty-nine patients,with a diagnosis of CHF consecutively admitted to three centers,were enrolled.M-mode echocardiography was used to determine the presence or absence of PE and to semi-quantify it.The 118 patients with PE and 472 without PE were followed up.The relationship between the PE and other parameters and the prognostic value of PE for CHF were analyzed by univariate and multivariate analyses.Results After following up,550 patients were analyzed,of which 226 were dead.The incidence of PE was 9.92％.Moderate PE was the most common which account 90.68％ (107/118).The 6.78％ of the patients (8/118) had small while only 2.54％ (3/118) had large one.The systolic blood pressure (OR=1.04,95％ CI (1.01-1.07),P=0.08),left ventricular ejection fraction (LVEF) (OR=1.09,95％ Cl (1.02-1.15),P=0.06),and main pulmonary artery diameter (MPAD) (OR=1.51,95％ Cl (1.24-1.85),P ＜0.001) were the independent predictors of PE.The glomerular filtration rate (GFR) (OR=1.013,95％ Cl (1.005-1.026),P=0.02),systolic blood pressure (OR=1.02,95％ CI (1.00-1.03),P=0.015),LVEF (OR=1.08,95％ CI (1.04-1.12),P ＜0.001) and diabetes mellitus (OR=3.53,95％ CI (1.99-6.44),P ＜0.001) were determined as the independent predictors of CHF prognosis.Conclusions The PE is not uncommon in CHF patients and most PE are small to moderate.PE is not related to the etiology of CHF while is strongly connected with higher systolic blood pressure,low LVEF and large MPAD.PE dose not increase the risk of death in patients with CHF.