OBJECTIVE To realize the circumstances of the antibiotic application during perioperational period and evaluate the rational application of antimicrobial agents in department of gastrointestinal Surgery in a hospital.METHODS Retrospective study for 210 patients in the department of gastrointestinal Surgery form Jan 2007 to Dec 2008 was carried out randomly.RESULTS The antibacterial agents were used in all patients during perioperation.The antibacterial agents used most frequently were Metronidazole and Cephalosporins,The combined use cases accounted for 90.5%.The average period of treatment was 7 days.The incidence of surgical site infection was 8.6%.Only 55.6% patient′s samples were examined and drug susceptibility test were detected.CONCLUSIONS The irrational applications of prophylactic antibiotitcs during the perioperative period are serious,such as the average time of using antibiotics was too long,unreasonable frequently sort changing and low rate for samples detecting.