Efforts to prevent IUU fishing began in 1996 as the IUU Antarctic Marine Living Resources Conservation Committee reported the multilateral efforts of the international community and related international organizations to prevent IUU fishing. Korea has recently been pointed out by the international community as to many problems regarding its will to eradicate IUU fishing. It is true that Korea has ever been designated as an ‘IUU participating country’ or a ‘non-cooperative third country’ by the international community and that there have been considerable difficulties in exporting seafood and using ports along with the deterioration of the national image. In 2020, with the efforts of related organizations and fisheries companies, Korea is now free from being known as a that Korea has recovered some degrees of trust from the international community through strengthening legal sanctions against IUU fishing and thorough implementation of follow-up measures is now free from non-cooperating country it cannot be said that the basic problems have been completely resolved just because it has emerged as a disgraceful country, and the current state of IUU fishing of Korea leaves a room for designation as a ‘non-cooperative third country’ again at any time in the future. Accordingly, there is an urgent need to examine the problems of the IUU fishing-related legal system in Korea and to come up with an improvement plan. Therefore, this paper reviews international norms for IUU fishing regulation (PSMA etc.) and domestic laws with the Distant Water Fisheries Development Act and Propose the improvement methods for related legal systems in Korea.