This study aims to estimate the consumption of antibiotics in Korea and to suggest the further studies. To measure the amount of antibiotics consumption, we referred to the statistic of NFHI(National Federation of Health Insurance) and a private institute of pharmaceutical information(Korea Intercontinental Medical Statistics; IMS Korea). There were 1,563 antibiotics produced in Korea in 1997. The total amount of antibiotics production was 1,197 billion won in 1997. Antibiotics accounted for 17.6% of the total pharmaceutical productions in 1997. Cephalosporins have taken the largest part of antibiotics production since 1992. The estimation using NFHI data showed that the total expenditure of antibiotics used in health facilities was 268 billion won, 608 billion won, 911 billion won in 1990, 1994, 1997 respectively. Tertiary hospitals spent 246 billion won, general hospitals 287 billion won, hospitals 78 billion won, clinics 300 billion won in 1997. The amount of expenditure and the intensity of antibiotics consumption in hospitals have increased more steeply than any other health facilities. The total expenditure of antibiotics consumption in health facilities and pharmacies was 778 billion won when estimated using the data from IMS Korea, and 999 billion won from NFHI. Cephalosporins was the fast growing antibiotics group in all of the market- hospitals, clinics, pharmacies since 1991. To measure the amount and patterns of antibiotics consumption more precisely, a pharmaceutical monitoring or surveillance system is needed.