Abstract: OBJECTIVE To explore the characteristics of pathogenic bacteira causing postoperative pelvic infection in eldelry patients with gynecologic tumor and analyze the high risk factors. METHODS A total of 584 elderly patients with gynecologic tumor who were treated in the hospital from Feb 2012 to Jun 2015 were recruited as the study objects. The incidence of postoperaive pelvic infection was analyzed, the risk factors for the infection were observed, and the drug suscpeitlbtiy testing was performed for the pathogenic bacteira causing the infection. RESULTS Totally 82 strains of pathogenic bacteria were isolated from body fluid or vaginal secretions of 62 patients with the infection, including 22 strains of gram-positve bacteria, 53 strains of gram-negative bacteria, and 7 strains of fungi. The risk factors for the postoperaive pelvic infection in the elderly patienst with gynecologic tumor included age, operation duration, complilation with chronic diseases, history of preoperative infectioud diseases, surgery mode, preoperative chemotherapy, postoperative use of antibiotics, postoperative catheter indwelling, and postoperative bedridden time. CONCLUSION There are a variey of risk factors for the postoperative pelvic infection in the elderly patients with gynecologic tumor. Focusing on the risk factors it is necessary to reasonably use antibitoics so as to improve the therapeutic effect.