OBJECTIVE To analyze the effects of centralized volume-based procurement policy （hereinafter referred to as “centralized procurement”） on the use of anti-tumor drugs in medical institutions. METHODS The interrupted time series model was used to analyze the changes in the monthly purchase volume and purchase amount of docetaxel， gemcitabine and pemetrexed disodium in a third-grade class-A cancer hospital in Shanxi province from January 2018 to December 2021. RESULTS & CONCLUSIONS After the implementation of the centralized procurement policy， both the selected drugs and the non-selected drugs had different degrees of price reduction， and the price reduction of the selected drugs was far greater than that of the non- selected drugs； average monthly purchase volume and amount of docetaxel decreased significantly in that month after the implementation of the policy， while those of gemcitabine and pemetrexed disodium increased significantly （P＜0.05 or P＜0.01）. After the implementation of the policy， the average monthly purchase volume and amount of gemcitabine showed a downward trend， while those of docetaxel and pemetrexed disodium showed an upward trend （P＜0.05 or P＜0.01）. It is suggested that hospitals should strengthen pharmaceutical administration， and avoid adopting a “one size fits all” approach to non-selected drugs； relevant departments should further expand the collection range of anti-tumor drugs or carry out special collection of anti-tumor drugs， so as to save medical insurance funds and reduce medical expenses.