The discriminating power of journal evaluation criteria of Korean medical journals were measured. The study used the data of 76 medical journals, collected in the "Korean Medical Journal Evaluation" process conducted by the Korean Association of Medical Journal Editors (KAMJE) between 1997 and 1999. For each evaluation criterion, the distribution of the individual score vs the total score of a journal received was plotted and their correlations were analyzed. It is found that the evaluation criteria with a high discriminating power are the ones associated with the peer review system and the journal editing. The evaluation criteria with a low discriminating power are the journal frequency and how often a chief editor is changed. Some evaluation criteria such as "Journal holding rates of medical libraries" and "year-end index" need modifications in the evaluation methods. Other evaluation criteria such as "Journal self-citation rate","SCI citation rate" and "SCI impact factor" need to modify the score ranges. It is recommended that the new evaluation criteria such as "citation rate by Korean medical journals" and "Access availability of the journal information through major Korean medical abstract databases" should be added.formation through major Korean medical abstract databases" should be added.dded.