ObjectiveTo investigate perioperative antimicrobial prophylaxis in thyroid operation at all levels of hospitals in a province.MethodsFrom January 1,2011 to December 31,2013, all kinds of thyroid operation in a province were conducted targeted monitor,  investigated results were analyzed.ResultsA total of 1 304 cases of thyroid operation were investigated, 1 294 (99.23%) were elective operation; duration of operation of  1 051 cases (80.60%) were ≤2 hours; antimicrobial use rate was 96.70%; 196 patients (15.45%) were administered 30 minutes before operation, 887 patients (70.34%) used antimicrobial agents for >48 hours; 19.53% of patients used the first generation cephalosporins and clindamycin.ConclusionThere are some problems in antimicrobial use in thyroid operation in this province, such as inappropriate choice of antimicrobial agents, improper administration time， long time use of antimicrobial agents， and use antimicrobial agents without indications. Management of antimicrobial agents should be strengthened, so as to promote the rational use of antimicrobial agents.