Climate change is one of the most influential factors on the range expansion of southern species into northern regions, which has been studied among insects, fish, birds and plants extensively in Europe and North America. However, in South Korea, few studies on the northward range expansion of insects, particularly butterflies, have been conducted. Therefore, we selected eight species of southern butterflies and calculated the potential species richness values and their range expansion in different provinces of Korea under two climate change scenarios (RCP 4.5 and RCP 8.5) using the maximum entropy (MaxEnt) modeling approach. Based on these model predictions, areas of suitable habitat, species richness, and species expansion of southern butterflies are expected to increase in provinces in the northern regions ( >36°N latitude), particularly in Chungcheongbuk, Gyeonggi, Gangwon, Incheon, and Seoul. In comparison to the current rate of habitat expansion, those in 2030, 2050, and 2080 were estimated to be 51.07 ~ 209.26%, 74.23 ~ 264.15%, and 62.32 ~ 858.95% higher, respectively. Our study revealed that southern butterflies are susceptible to climate change and that the northern habitat margin of southern butterflies is shifting northward.