OBJECTIVE：To establish quantitative e valuation system of the prophylactic use of antibiotics in orthopedic type Ⅰ incision surgery ，and to provide reference for evaluating the rational prevention use of antibiotics in this type surgery scientifically. METHODS：Based on the Guidelines of Clinical Use of Antimicrobial Agents （2015 edition），drug instructions ，related guidelines and references ，experts from relevant departments jointly discussed and formulated the evaluation criteria for the rationality of the use of antibiotics in type Ⅰ incision in orthopedic surgery. AHP method was used to assign the weights for various indexes of evaluation criteria ；TOPSIS method was used to retrospectively analyze and evaluate the rationality of 120 cases of type Ⅰ incision surgery from 3 orthopedic departments in Peking University People ’s Hospital during Sept. 1st-30th，2019. RESULTS ：Established evaluation system included 4 primary indicators （medication indication ，usage and dosage ，medication timing ，other factors ）and 12 secondary indicators. Among the secondary indicators ，indications，drug selection and timing of preoperative administration were the most important （weights were 0.209，0.140，0.117）. Among 120 cases，30.83％ of drug use were reasonable ，47.50％ were basically reasonable and 21.67％ were unreasonable. Evaluation results obtained by AHP-TOPSIS were consistent with the actual situation. CONCLUSIONS ：The rationality evaluation method of prophylactic use of antibiotics in type Ⅰ incision surgery based on AHP-TOPSIS method can quantitatively evaluate the rationality of drug use by combining multiple indicators. The method is feasible ，operable，and the evaluation results can be quantified ，which has a wide range of application.