Objective: The paper attempts to study the impact of national centralized drug procurement on the stock prices of pharmaceutical listed companies. Methods: Using the event study method, nine batches of centralized drug procurement policies were taken as the research objects, and the impact of centralized drug procurement policies on stock prices was explored from the perspectives of selected enterprises and pharmaceutical industry. Results: The results showed that after the occurrence of each batch of centralized drug procurement, the stocks of the selected enterprises and pharmaceutical industry index produced significant abnormal returns. In terms of stock price, the policies had a negative impact on the selected companies to some extent and an overall positive impact on the pharmaceutical industry in the short term. However, this study did not compare selected drugs with the drugs that were not selected and did not participate in the centralized drug procurement. There is also no comparative analysis of stock price changes with other industries in the capital market. Conclusion: The study believes that the stock prices of the selected companies and the inverse movement of the pharmaceutical industry index lead to some arbitrage space, which is a good opportunity for long-term value investors to build positions. It is suggested that government departments should adhere to the normalization of the centralized drug procurement system, strengthen quality management and cost control of pharmaceutical listed companies, and cultivate a rational value investment concept among investors in the securities market.