Abstract — This study aimed to assess the quality of outpatient antibiotic consumption in Korea compared with other coun- tries. We used the National Health Insurance claims data for outpatient services in March, June, September, and December in 2012 and calculated nine indicator values based on the 12 European Surveillance of Antimicrobial Consumption (ESAC) drug-specific quality indicators. Indicator values in this study reflect the yearly use of antibiotic expressed in defined daily doses for 1,000 inhabitants per day (DID) and the use of main subclasses of antibiotics expressed in DID and as percentage of the total antibiotic use. Korea showed lower quality in the consumption of total antibiotics (J01), especially in the use of Cephalosporins (J01D) expressed in DID. Korea also showed low quality with regard to the use of narrow/broad spectrum antibiotics. The percentage of the use of narrow-spectrum Penicillins (J01CE) was lowest in Korea. The quality on the use of the third- and fourth-generation cephalosporin (J01(DD+DE)) was the fourth lowest among 26 countries. High rates of antibiotic resistance and payment system based on fee-for-service might have influenced on the high consumption of the broad spectrum antibiotics in Korea. It needs to further investigate the use of broad-spectrum antibiotics to identify the target of strategies promoting quality use of antibiotics in Korea.