Abstract: OBJECTIV To analyze the distribution characteristics and cardiac function of pathogenic bacteria in patients with infective endocarditis (IE) and summarize the clinical characteristics of infected patients, so as to provide the basis for clinical diagnosis and treatment of IE. METHODS A total of 127 patients with IE from Jan. 2011 to Nov. 2015 were retrospectively analyzed, and were divided into positive group and negative group according to bacterial culture results. The results of pathogen identification of IE patients were analyzed and compared. The differences of the indexes of cardiac function and infection between positive and negative blood cultures were compared. RESULTS In the positive group, the main pathogens were gram-positive bacteria. The infection rate of Streptococcus was the highest (59.3%), followed by Staphylococcus aureus (14.8%). The serum LVEF, FS, LVEDD, WBC, LY, NEUT, HGB, ERS, and CRP in the blood culture positive group were significantly higher than those in negative group. Logistic regression analysis showed that cardiac history and cardiac chelator were independent risk factors for IE(P<0.05). CONCLUSION The major pathogens of IE are gram-positive bacteria, and the differences of heart function and infection degree among IE patients with different blood culture results are significant. It is suggested that the blood culture pathogens should be actively identified, and the changes of cardiac function and serum infection indexes of positive infection should pay attention to accurately assess the outcome of the disease.