This study was conducted to compare protected areas of South and North Korea based on international conservation criteria and recommend new fundamental directions for nature conservation policy. International conservation criteria used by this research were the 1994 IUCN protected area categories, composed of 6 management categories. Despite a variety of types and names of protected areas created by different domestic legislations, South Korea was revealed to have only two types of protected areas, Category Ⅳ and Ⅴ, indicating the significant lack of ecological diversity and representativeness in its protected area system. Shockingly, there are no national parks meeting IUCN criteria in South Korea. On the other hand, North Korea has three IUCN Categories of Ⅱ, Ⅲ, Ⅳ and thus more balanced and ecologically representative protected area network than South Korea. Especially, North Korea maintains 9 national parks to be officially recognized by IUCN and UN. However, both South and North Korea should make sincere effort to have new and well-designed protected area system including all IUCN Categories Ⅰ-Ⅵ and particularly a minimum area in the stricter protected area categories.