ObjectiveTo find out the etiological factor characteristics and age composition of pericardial effusion,to improve clinical diagnosis and treatment,reduce the misdiagnosis rate. Methods73 pericardial effusion patients in our department were admitted by age into youth group, middle age group and elderly group, and the etiological factor characteristics and age composition of pericardial effusion were analyzed respectively. ResultsThe main pathogenic factors of 73 pericardial effusion patients were cancer, heart failure, tuberculosis, non-specific pericarditis, nontuberculous bacterial infections, as well as renal failure, pulmonary infection, trauma, myocarditis, acute myocardial infarction, collagen disease, hypothyroidism. There was statistically significant of etiological factors on the three groups (P ＜ 0.01 ). ConclusionPathogenic factors of pericardial effusion were affected by many factors, and the significant difference in age composition should be well focused in clinical practice.