Objective To investigate the use of antibacterials and to analyze the cases of irrational use of antibacterials in this hospital, providing reference for clinicians and promoting the rational use of antibacterials. Methods The expenses of total drugs and antibacterials from 2011 to 2012 and the retrospective investigation of medical records of in-patients were performed in this hospital. Rationality of antibacterials use was analyzed and evaluated. Results The rate of antibacterials expense in department of urology was 44.15%, and the next was department of generalsurgery (41.52%). 2994 inpatients’ medical records were investigated, of which 1886 recorded use of antibacterials(62.32％) and 906 exhibit a irrational use of antibacterials (48.55％). Conclusions The rate of antibacterials use and drug expenses in this hospital are high and the various irrational uses exist. Potent countermeasures needed to be adopted to decrease the irrational use of antibacterials.