To understand the characteristics of open access journals in Korea, this research examined the 1,438 KCI journals in the fields of humanities, social sciences, natural sciences, engineering, medicine, agriculture & oceanography, art & sports, and interdisciplinary. 21% of the KCI journals are freely available at the publisher's websites or open access DBs(OA). 34% are available only in the commercial fulltext DBs(TA) and 34% combined TA and OA. 48% of the OA journals can be found on the free fulltext DBs and 52% are accessed on the publisher's websites. OA journals in humanities and social science are available mainly on the publisher's websites. As compare with this, OA journals of STM fields are available via the free fulltext DBs. Medicine(30%) and social sciences(25%) have the highest overall share of OA. There are field differences in the rate of OA journals. In the fields of social sciences and humanities, 15% of the journal are open access. In case of medicine field, 60% are open access journals. OA journals in natural science and engineering are each 33% and 24%.