OBJECTIVE： To provide reference for the further improvement of the drug purchasing system in Chongqing city. METHODS： 30 primacy medical and health institutions in Chongqing were selected to collect the data about cost changes and business development in above-mentioned institutions from 2009 to 2013， the purchasing price， use and supply of essential medicines were collected via Chongqing Municipal Health and Family Planning Commission to evaluate and analyze the effects and existing problems of drug purchasing system， and suggestions were put forward. RESULTS： Compared with 2009， the non-essential drugs’ prices fell an average of 28.00％ in 2013， prices of 307 varieties in National Essential Medicine System （2009 edition） fell an average of 32.97％， 205 varieties in supplementary list of local prices fell an average of 43.78％. The proportion of sales amount （not including Chinese herbal medicine） in primacy medical and health institutions increased from 76.48％ in 2010 to 92.07％ in 2013， the average rate of essential medicines increased from 6.84％ to 28.12％. Compared with 2009， the average drug cots and inpatient drug costs decreased 16.78％ and 25.85％ in 2013， the proportion of drugs decreased from 56.32％ in 2009 to 49.70％ in 2013. CONCLUSIONS： Generally speaking， the implementation of drug purchasing system in Chongqing is successful， but also exists some problems， such as imperfect pricing mechanism， difficult supply of low-cost drugs， slow rise of average outpatient costs in primacy medical and health institutions and irrational drug use. It is suggested to improve it from aspects of perfecting drug pricing mechanism， optimizing logistics and distribution， strengthening the role of the medical insurance institutions， regulating medication overuse and improving compensation policy of medical institutions.