Abstract: Objective To analyze the pathogenic and drug resistance features,as well as laboratory indices,of spontaneous bacterial peritonitis( SBP) and to provide a basis for the early warning,rapid diagnosis,and timely treatment of the disease. Methods The clinical data and laboratory indices of 1340 patients diagnosed with SBP in 302 Hospital of PLA from January 2011 to December 2013 were retrospectively analyzed. The pathogenic spectrum and laboratory characteristics of SBP caused by different pathogenic bacteria were compared and the drug resistance features of the bacteria were also determined. Drug sensitivity results were analyzed with WHONET5 software,and statistical analysis was carried out with CHISS software. Comparison of continuous data was made by t test,and comparison of categorical data was made by chi- square test. Results Of the 1340 liver cirrhosis patients with SBP,591 cases( 44. 10%) were infected with gram- negative bacilli( G- b),746( 55. 67%) with gram- positive cocci( G+ C),one( 0. 07%) with fungi,and two( 0. 15%) with gram- positive bacilli( G+ b). Compared with G+ Cinfection,G- binfection involving other body parts had a significantly higher abnormality rate of laboratory indices including neutrophil,ascites white blood count( WBC),polymorphonuclear leukocyte( PMN),alanine aminotransferase( ALT),aspartate aminotransferase( AST),total bilirubin( TBil),exogenous prothrombin activity( PTA),and creatinine( Cr)( P < 0. 05). The positive rates of extended- spectrum beta- lactamase( ESBL) produced by Escherichia coli and Klebsiella pneumoniae were 40. 00% and36. 03%,respectively. The drug resistance rates of Acinetobacter baumannii to amikacin,sulfamethoxazole / trimethoprim,and imipenem were 42. 42%,57. 57%,and 57. 58%,respectively,while the drug resistance rates of Pseudomonas aeruginosa to cefoperazone and ticarcillin / clavulanic acid were 45. 45% and 36. 36%,respectively. The composition ratios of methicillin- resistant Staphylococcus aureus and methicillin- resistant coagulase- negative Staphylococcus were 43. 33% and 78. 09%,respectively,and their sensitivity rates to vancomycin and teicoplanin were 100%. Conclusion The pathogenic bacteria of SBP were mainly G+ Cand G- b,which show strong drug resistance. Auxiliary examinations for neutrophil,ascites WBC,ascites PMN,ALT,AST,TBil,PTA,and Cre can predict G- binfection,and antibiotics should be used in the treatment based on the types and drug resistance of pathogenic bacteria as well as the patients' conditions.