Abstract: OBJECTIVE To investigate and analyze trend and change of antibacterials in 47 tertiary hospitals of JiangSu Province from 2012 to 2016, and provide empirical evidence for rational use of antibacterials in clinic. METHODS The antibacterials used in 47 hospitals were investigated and analyzed, including defined daily doses(DDDs), the defined daily cost(DDC), the ranking ratio(B/A). RESULTS The sum of money of consumption of oral antibacterials, injectable antibacterials, total antibacterials and DDDs of injectable antibacterials had a growing trend. The DDDs of oral antibacterials was about twice that of injectable antibacterials. The amount of money spent on penicillin β-lactam antibacterial(J01C), other β-lactam antibacterials(J01D) and other antibacterials(J01X) increased from 2012 to 2016, and the DDDs of J01C increased. J01D accounted for the highest proportion of the sum of money, and stabilized at about 65%-67%, which had the highest DDDs. Among the top 10 antibacterials in the sum of money, the most drugs belong to third-generation cephalosporins(J01DD) and the highest DDC was biapenem. CONCLUSION Most of the different kinds of antibacterials in the DDDs and sum of money used remained stable between 2012 and 2016, but some of the antibacterials have upward tendency, and medication is too concentrate. DDC of some antibacterials is relatively high, and there is a wide gap between DDC of different drugs.