〔Abstract〕 Rationality of perioperative prophylactic use of antibiotics in class I incision is an important index of hospital pharmaceutical administration. Lean management tools [such as flow chart, Plato, fishbone diagram, standard operation procedure (SOP), etc.] were used to identify the four key links of the prophylactic use of antibiotics in the clean operation. Root causes were analyzed through key links, and a series of targeted improvement measures were taken with the cooperation of physicians and pharmacists. The prophylactic utilization rate of antibiotics decreased from 52.35% in October 2021 to 36.73% in September 2022, and the SOP of key department was established. The timing, drug selection and duration were also significantly improved. The application of lean management tool can effectively and sustainably improve the rationality of prophylactic use of antibiotics in class I incision.