The aim of this study was to reveal whether there were differences in the understanding of scientific models according to their conceptions of lunar phases. The participants were 252 10th grader in South Korea. They were asked to respond SUMS (Students Understanding of Models in Science) instrument and to draw and explain why the different lunar phases occur. Students' conceptions of lunar phases were analyzed qualitatively based on established criterions and the differences in the perception of scientific models, a one-way ANOVA was conducted. Results indicated that Korean students' conceptions of the lunar phases were classified into five types: scientific, alternative, incomplete, eclipse explanation, and naive conception. The participants appeared to have different epistemological perceptions concerning each of the five sub-factors in the scientific models. The students with a scientific conception of lunar phases tended to understand that multiple representations could be used to express the different dimensions of an object. It was found that Korean students have a good understanding of the role of models as explanatory tools(ET) and the changing nature of scientific models(CNM). There was statistically significant differences were shown in ET, USM(uses of scientific models) and CNM factors depending on the types of conceptions of the lunar phases.