OBJECTIVE： To analyze intervention effect of Drug Rational Usage Guidelines System （DRUGS） on antibacterial agents use in department of obstetrics and gynecology in our hospital. METHODS： The application of antibacterial agents in department of obstetrics and gynecology in our hospital during Jan.-May （before intervention）and Jun.-Nov. 2012（after intervention）were extracted in respects of drug name， preoperative medication duration， perioperative additional condition， postoperative drug withdrawal time， drug combination， usage and dosage， average hospitalization stay， hospitalization cost. The intervention effects were analyzed. RESULTS： After intervention， the type of antibacterial agents were more in line with national regulations； the proportion of type Ⅰ incision surgery without antibacterial agents increased from 57.8％ to 75.2％； the prophylactic application of antibacterial agents in type Ⅱ incision surgery within 0.5-2 h increased from 80.2％ to 97.0％. The rate of reasonable antibacterial selection， drug combination， usage and dosage increased from 76.9％， 64.9％， 71.3％ to 89.3％， 84.6％， 90.2％， respectively. The average hospitalization stay and antibacterial cost per capita decreased significantly. There was statistical significance among above indicators before and after intervention （P＜0.05 or P＜0.01）. CONCLUSIONS： DRUGS effectively change irrational use of antibacterial agents in department of obstetrics and gynecology， which provide a new method for the management of antibacterial agents.