We use the event study method to assess the impact of China's National Centralized Drug Procurement (NCDP) policy on the stock price of A-share listed companies in pharmaceutical industry. And the empirical evidence reveals that the policy has a negative effect on the share prices of firms won the bids in the past six centralized procurement. The stock prices of winning bidders were more negatively affected than those of non-winning bidders. If the winning bid price continues to be depressed, we cannot rule out the possibility of a collective abandonment of bidding by quality manufacturers.