As urbanization becomes widely spread, environmental benefits of natural landscapes have been highly appreciated. The social demands to conserve such landscapes are becoming stronger in modem society. In order to effectively manage natural landscapes, one should know what natural landscapes are. The characteristics of natural landscapes revealed by foreign research include wilderness, absence of human intrusion, and presence of diverse natural element (plants, trees, waters). The purpose of this paper is to investigate the characteristics of diverse natural landscapes with different levels of naturalness. The methods adopted here consist of three phases. First, 368 landscapes were photographed to include different levels of naturalness. Second, two professional landscape groups assessed the degree of naturalness of the collected landscapes, in which the characteristics of five degrees of naturalness were examined. Lastly, undergraduate students, as laypersons, assessed the 33 landscapes that were selected as representative of the five degrees of naturalness. The results show that there is no difference between professionals and laypersons on the assessment of naturalness of landscape. The characteristics of natural landscape that participants perceive include no human intrusion, preservation of original state, traditional quality such as Korean-style architecture, dominance of natural elements, and minimum facilities that harmonize with natural surroundings, Many characteristics are similar to the results of foreign research, However, the results reveal that Koreans do not perceive man-made nature as natural, while they perceive traditional elements as natural. Based on the results, some suggestions for landscape management are presented in the conclusion section.