Objective: To analyze the impact of national drug centralized procurement policy on the sales volume，sales volume，drug brand，frequency of use，substitution rate of generic drugs，drug price，average daily cost and potential cost savings of selected antibacterial drugs，explore the implementation effect of centralized procurement of antibacterial drugs and put forward policy recommendations，so as to provide references for improving the rules and supporting policies of centralized procurement of antibacterial drugs. Methods: The sales data from the first quarter to the third quarter from 2020 to 2021 of 6 selected antibacterial drugs collected in the third batch were selected，and the implementation effect of centralized collection of antibacterial drugs was analyzed by descriptive statistics. Results: The national drug centralized procurement significantly affected the scale of the antibacterial drug market and reshaped the competitive pattern of the antibacterial drug market; change the behavior and structure of antibiotics; it will affect the price of each brand of the selected variety and significantly reduce the cost of medication. Conclusion: The centralized purchase of antibacterial drugs has achieved remarkable policy effects. Based on the particularity of antibacterial drugs，it is necessary to focus on the relationship between the effect of the national centralized purchase policy of drugs and the rational use of antibacterial drugs.