Recently, the use of electronic drug information databases has been increased alternative to printed references. However, databases vary widely in quality and quantity of drug information provided and many questions have arisen about their accuracy, completeness, and reliability. This study was designed to compare and evaluate the drug information contained in four Korean drug information databases which are available on CD-ROM and internet. Four Korean drug information databases selected to be evaluated were eKIMS, Datapower, KPA Standard Drug Information and Korean Drug Formulary. Databases were searched and evaluated from August 10 to September 30, 2000 by the same trained searcher to minimize the bias. The database evaluation form was developed for objective evaluation of each databases in terms of credibility of database, convenience of use and other characteristics. The second form was developed for quantitative and qualitative assessment of the drug information provided by the databases. The results of the study showed that there were no significant differences in 4 databases in terms of convenience of use and other characteristics. However, for credibility of databases, Korean Drug Formulary was significantly superior to all other databases (P<0.05). It showed that information provided by Korean Drug Formulary was the best in terms of pharmacokinetics, chemistry, comparisons and eKIMS was the best in terms of drug identification (P<0.05). For accuracy and completeness of information provided, the study could not find a significant difference between 4 databases (P>0.05).